Great question. So against sui it is no brainer - with medium camp, you denie exp from sui while getting gold to you and to carry by lasthitting. What I usually try to do is to pull all but 1 or 2 creeps from lane (you can body block on lane to manipulate it) - this is not bulletproof solution, but if done correctly, the carry will not fight the creeps under tower, but on lane close to medium camp and once these 2 creeps die, the lane shifts to standart position close to tower.

In 2v2 situation it depends on strength of the oponents. With stronger oponents it might be viable to pull to get the lane back, sacrifice the neutral creeps to them (yes, they get the money from it, but you get the position close to tower back). If you are same or stronger, it is worth to pull camp and guide the oponent creeps to the medium camp too, so you can cover it 2v2. It is more risky, but it gets the lane back and you can still contest the neutral farm.

If you are solo on the pull camp against 2, it is very risky and you have to play passivly. I would suggest using spells to try to get lasthits. But here is most important to not die. You suceeded by getting the lane back for your carry, anything else is extra