Hi. By field presence I mean the fact that both the tank and pio are out of action. Pio is more than 200 manpower which means one gren squad or mg or mortar not on the field. As US you dont need to spend that manpower on that unit because you have the crew. You basically have many more other squads running around. Bear in mind that pios have other jobs to do such us building base structures which means thay can't cap at the same time. Think about when ost has 2 tanks. To repair them quickly U meed 2 pios which means over 400 manpower. Very often you simply dont have 2 pios on the field and Ur tanks must wait to be repaired one after another. Again crews in such situation are "get out of jail" solution. Better players are aware how important pios are and if they eliminate even one they affect ost tanks severely. Generally I can't agree with anything U wrote above. U don't seem to realise how powerful eg flame pios can be.
If a SU player is in need to repair a tank, both the tank and the engineer has to retreat too, same with OKW if you don´t have the T2 Build up (the one with the puma and free repairs)...
and of course, if you want to repair a sherman the sherman has to retreat to a safe spot...
So in the end, all factions has to retreat the tank, and only USF doesn´t need a RE to repair it....
That´s why your argument about field presence is wrong in my opinion, because this happens with any faction, if you want to reapir a tank, that tank has to retreat, not only the OST tanks has to retreat....so this left only the pio squad....come on, if your front line suffers because a pio squad is repairing a tank, your front line will suffer the same with the pio helping there...their figthing capabilities are really low man.....
And yeah, USF tank crews can repair by itself, but the tank cannot attack while being repaired if you use your crew to repair,while an P4 can shoot to targets while the pio is repairing.....and in addition, if you want to capture an abandoned tank as USF, you need to purchase a fresh RE squad for that (or loosing a rifle or other squad to use them as tank crew) while with any other faction, you use your cheaper volvks or pios or whatever and then reinforce the rest of the squad at your base...so USF is in a worse spot in that situation.
so USF tank crews have some advantages, but they have some cons too....and that´s why your arguments are wrong in my opinion and USF tank crews are perfectly fine.
anyway, noob here so only my opinion.