Im assuming your talking to me? I think PTRS penals are fine, I was giving suggestions based on what OP stated. I think their AI in the LATE GAME is slightly UP, but since you said that can you point to a high level match between elite players where the PENAL player won without either T2 back tech or Commissar.
I wasn't talking to anyone specifically otherwise I'd quote. I'm saying that penals as AT infantry is fine as is.
You won't see penals AT in high level 1v1s because you lose a lot of AI power if you change it up and 1v1s are quite tight when it comes to staying power/bleeding.
In 3v3+ I've seen PTSR penals being utilized to great effect. Usually 2x PTSR penals which hold the line against any and all dives, one ZiS and then the bulk of the force is either cons or elite infantry (usually cons). In 3v3, the mode which I play, I also see a skip of t70 (due to the massed AT guns in 99% of games).
Sometimes PTSR work, sometimes they don't. You won't see them often because they are a reactive force. You get them as a reaction to the enemy playstyle. If the enemy is not building mass light vehicles, don't go PTSR, but just tech t2 and get ZiS before minute 13 or a fast T34 if you can afford it.
Can't tell you how many times I've seen mass 222 plays from Ostheer, even top level players. I've seen a premade x3 top 5 3v3 team of three Ostheer players which made (I think) about 12 222s in first 10 minutes on Lienne forest. All 3 of them built 4.
The tactic was:
Bunker down on one side so you get stead income, don't bleed.
Start spamming 222s
Once you have 10+ 222s, you win the game.
Thank FU** that my soviet player had 2x PTSR penals with maxims. Their tactic went down the drain. If it wasn't for PTSRs we'd lose. AT guns are useless against such a mass due to their agility, and Rifles from me and my other teammate were useless. Heck, tried to snare 3 222s, all 3 rifles died before the snare even went off. The animation is something special. My AAHT somehow survived and managed to kill 2 222s (got extremely lucky). They surrendered promptly.
See, a reactive force.
You won't just go PTSR penals like you would go for a ZiS gun. You build ZiS because you expect medium tanks to hit the field and you need something with range to keep them at bay. You upgrade Penals with PTSRs to react to the enemy LV phase, not because you plan to counter a future P4 and get overrun by infantry in the meantime
When you build a ZiS, you gain a ZiS gun, losing NOTHING. When you upgrade penals, you SWAP AI for AT. Hence action-reaction