VSL is odd to be honest. If you want staying power just go Osttruppen who can also build their own sandbags which is already a massive disadvantage in terms of staying power for VSL.
Edit: typo
I see your point and I agree about Osttruppen, I just happen to really enjoy the Infantry Doctrine. Even if it is not the best I would probably continue to use it. But
that gives me an idea. Why not instead of free medkits VSL grens can place sandbags?
*edit
Otherwise imo it seems like if you pick the Infantry commander you just want the upgrade for panzer grenadiers and access to storm troopers while using lmg gren? I mean sure you can get fragmentation bombs so like there are some decent things in the doctrine still, but aren't there doctrines with access to that which gives you more things that are equally good but offer more?
Like elite troops especially now that g43 grens are buffed and that would also give you access to storm troopers and other good abilities
Or maybe you're better off using Strategic Reserves Doctrine. That gives your panzer gren access to smoke grenades too, instead of VSL Pios they have breakthrough upgrade which allow them to repair fast and stacks with the minesweeper repair just like it would with 5 man pios from Infantry Doctrine. But not only this you have access to a Panzer 4 Model J and Mobile Observation Post and Tiger Ace. And if you want to, Assault Gren are good too
Spearhead, if you're going to use lmg grens and you want fragmentation bombs you get access to recon, tiger and panzer tactician, mortar half track
I guess I just don't want to see Infantry Doctrine be useless and I could be wrong maybe it's still a good doctrine, but it seeems to me IMO that the doctrine has similar abilities in other doctrines that compete just as well if not better because VSL grens are no longer good. The point of the ability I think is to give you a better mainline option with your grenadiers. But again yeah, I could be very wrong, just thought I'd give some examples as to why I think this way, especially now that this commander update is close to going live, it would seem like they're trying to make more commanders to be viable choices so I am just hoping Infantry Doctrine remains a solid choice as well