Wouldn’t the combat doctrine of IFV differ from APC in the sense that PA M-113s are battle taxis, while M2 Bradley is a proper IFV, therefore M-113 will try to unload soldiers ASAP and reverse to assembly area whereas Bradley will keep carrying soldiers longer while engaging head on with enemy in direct combat.
What has actually upset me now is as follows :
1. US army infantry division operates IFVs while PA Mechanised formations still operate APCs.
2. M-113 is frontline weapon system for PA.
You are talking about stalling of Russian forces north of Kyiv ? The long convoy ?
We don't have a traditional APC role anymore after we move on from the M113, M2 Bradley is a IFV while M3 Bradley is a scout vehicle.
The doctrine different is mostly on how to advance alongside your Ironside (Armor) With Bradley, we move ALONG with the Abrams, either in a mix/match which mean we will have 2 M1 up front and 2 Bradley on either side, or in a phase line operation, which mean M1 is going to roll first, Bradley follow and brought up the troop. Bradley is being used as screen and security for Armor formation and its infantry are used as dismounted mechanised infantry.
Tradition APC doctrine is to bring in troop after the area is secured by any firepower you have. Basically it's the same as inserting infantry in any other way (like Air Assault or bring in with Truck) In today US Military, that roles goes to M1126 Stryker, it can carry similar troop configuration (IIRC it's 9) and we called them Infantry carrier, they are used for Infantry Assault when you bring in 9 Stryker (45 men, a platoon), Which mean APC is used for Infantry Support, while Bradley used more like mechanized infantry and used for Armor support.
M113 would probably used in PA the same way we use Stryker. I supposed.
I am not familiar with how PA Armor regiment work, but conventionally, you would want something more heavily armed and armoured to travel with your tank and act as Mech Infantry to provide support and security of Armor, but you will also need troop carrier that can deliver troop safely and exploit any gain with your armor regiment..
In short, if PA don't have a designated IFV, you probably need to get one.