Imagine abrams have different behaviours and buttons to press to what these chaps are used to. Different weight class, handling, aiming, reloading, maintenance. You don’t need tank v tank combat experience to educate people who don’t necessarily speak English fluently which button does what, where it is and when/how to use tank gadgets so it goes into muscle memory because i donno about you, but if someone starts shooting me out of a tank i am very likely to piss myself. Its better they learn muscle memory of where what is in those tanks to be effective and hopefully soon we can see these chaps rolling into Crimea.