Solo vs duo laning is not uncommon in bronze-low plat ranks, either due to lack of roaming supports or just teammates who just refuse to switch which result to 1v2/2v1 side lanes.

I oftentimes experience it soloing so I wrote my thoughts about it.

1v2 (solo vs duo)

“I’m not locked up in here with you. You’re locked up in here with me.” — Rorschach

I once had a game where our level 3 Murad ganked top while I’m 1v2’ing.  I was doing rather fine on my own, even getting last hits on creeps and stealing the vision bird, up until Murad decided to gank without ult.  He gave up a kill and then went back for another gank and died again. Yes, I appreciate his willingness to help but not every 1v2 lane needs helping, especially that early.  Being a tank player, I personally prefer 1v2.

Some players seem to think that tower hugging = losing. It is not. As long as your tower is intact and the enemy duo is kept in lane and not rotating, you’re doing fine. Tower hugging actually has some advantages:

•  It gives room for outplays. If the opponents decide to dive, characters with good cc can easily nullify the attempt and get a kill instead. I’ve gotten double kills with this.
•  It allows teammates to have numbers advantage. With one going 1v2, the other 4 players are free to do whatever they want in the map. The best part of this is the 4 can easily collapse on the 2 opposing laners when they are extremely overextended.
•  It starves the opposing laners of gold and XP. Since they are sharing farm and gold, they are actually gimping themselves especially if they are not getting a kill or tower in exchange.  Time is your friend here.  The longer they stay in lane, the more they severely gimp themselves in the process, especially if they’re not achieving anything.

On paper, the idea is to create a birdcage that would make the opposing duo stagnant on top.  The longer you’ll be able to make them stay in lane without any significant gains, the better your chances are. 

As the solo laner, you should try to abuse your advantages. Still, take extreme precautions as chances are the enemies will try to use their advantage too, so here are some tips for 1v2:

• Be reactive.  You’re not the aggressor so you’d have to adapt, be it item-wise or macro-wise.  Always check minimap for missing laners.  Fighting against 2 is already bad enough, allowing more enemies to join is plain suicide.
• Play defensively, but don’t be a pushover.  Always try to clear the wave.  Having a wave crashing to your turret not only results to losing it but also ways for your opponent to tower dive.  You can get Heart of Incubus to help speed up waveclear and provide armor too.  Build defensively.  Sometimes you’ll be even be forced to get varying components for survivability (e.g., Knight plate + Heart of Incubus).  If using skills to clear waves, to try hit the enemy heroes too to harass them at least.
• Be enticing.  Make it worth their while staying together on your lane.  If possible, make them think that will get a kill from you.

• Manage your resources (HP/mana). Don’t use your skills to unnecessarily harass opponents. Only do so when you’re certain that your team has a way to get the kill. If ever you’re able to chunk your opponent, try to ping your teammates.  If the opposing laner/s become too low while your teammates are busy to gank, you might miss the opportunity to take them down.
• Be wary of hero skills. Some heroes like Arum are good at diving and can kill you outright under turret.  Time your skills too.  It’s better to wait for the opponents to take tower aggro before firing up your own cc’s.
• Try to communicate.  This is my mistake on the above example.  I should’ve mentioned earlier that I can handle the lane and I’d just ask for help when needed.  Proper communication can make your teammates take advantage of your 1v2 lane.  Ping when the enemy goes missing. Always warn your teammates of missing enemies. If you’re planning to respond, try to quickly clear the wave.
• Avoid facechecking brushes.  This is a no-brainer.  The enemy could be faking a rotation to bait you into an ambush.
  
• If the opposing duo goes missing and appears elsewhere in the map, spam retreat and shove the lane hard.  Chances are you’re too late to respond anyway so better take advantage of the undefended lane.  If you think you can still respond, do so but don’t leave the lane if waves are pushing towards you.
• If the tower is about to fall due to sheer numbers, just give it away.  There is no sense giving away your life for it as they’ll be able to take it after killing you.

Take note though that 1v2 depends much on hero choice.  Some heroes have better survivability in 1v2 situations like Maloch or Chaugnar  while some heroes are poor 1v2ers.  Usually, waveclear is the main factor here.

2v1 (duo vs solo)

“Fighting without an army is called a duel, and you’ll lose a duel if your enemy comes expecting a war.” –Gerrard of the Weatherlight

2v1 laning is not uncommon in Bronze-Plat (sometimes you’d even get 2v2 sidelanes when no one wants to jungle but that’s a different case).  When I have to fill for jungle, I often pick a “support jungle”, as I lack the mechanical skills to play an assassin.  I just start red, and tell my friends who love to duo to get the blue buff and run it down mid. It’s not easy going solo against duo Violet with a blue buff (Blue Violet) and Alice. Our “duo mid” often ends up tearing the opposing mid apart while offering a good area of security for dragon and slayer.  Their usual tactic is to just shove and roam.  We’ve tried this strat up to around low plat.

Having the numbers advantage doesn’t mean you can easily crush your lane.  In the process, you are severely hurting 2 members of your team.  Because of this, I AM NOT RECOMMENDING ANYONE TO DUOLANE.  But if you insist on doing so, here are some pointers:

• Be highly proactive.  I insist on being highly proactive.  Time is your enemy. The longer you stay duo in lane, the more your numbers advantage drops. Remember that you are splitting gold and XP, so your solo opponent would eventually be of a higher level than you. Always find ways to get gold/XP like counterjungling and/or finding ganks.  Shove and rotate.  That’s the only way to make it work.
• Play aggressively but be wary of the map.  Most players hate 1v2 and will likely ask teammates for help.  Sometimes they’d even tilt and make misplays, so try to kill the solo laner if possible.  Since you have the numbers advantage and duo comp, this can be easily done.  A poke duo can just whittle the solo laner until he/she is in kill range.  A dive duo can well, attempt a “tower crash dive.”  This is done by waiting for a huge wave to push into the tower and then diving the opponent for a kill.  You’d have to juggle aggro though.  After a kill, remember tip #1 and be proactive. Take a turret or an objective. Don’t waste your time to force a kill.
• Shove and rotate.   As stated above, this is the only optimal way to play 2v1. Clear the lane and move around the map.  Take the enemy jungles.  Again, don’t waste time to force a kill, and never force push a turret especially if the enemy has good waveclear.  This is the most common mistake of a duolane (aside from duolaning itself).  Just let the minions do the chunking and finish it off when it’s low enough.
  
• Control the brushes.  The brush offers not just terrain advantage but also allows for psy-war tactics. Popping in and out of the brush while throwing skills in between can be pretty tilting.  You can even fake a rotation and hide in the brush to ambush the opposing laner if he/she attempts to rotate.
  
• Utilize the support items.  Lane support items (water) provide additional XP and gold to somehow mitigate duo lane tax a bit.  This is the scenario where I think these underutilized items can shine more than their wind counterparts.  Even they are tagged as “lane items”, you don’t have to necessarily stay in lane to make good use of them.  You can still roam during the window that the stacks are on cooldown.

If the soloing player is likened to a birdcage, your duo on the other hand is a bird of prey.  You should act like one and overwhelm your opponent with your early advantage.  Again, time is your enemy.  I cannot just stress this enough.

My duo laning experience can be summed up in this strategy post.

All in all, whether it’s 1v2 or 2v1 or just regular 1v1, what matters most is learning to adapt as strategies evolve and gaming experience in the Arena varies, most especially if you want to climb.

Observe.  Formulate.  Adapt.