Here's the thing though, if your opponent has enough fuel to call in 2 or 3 is2s once they have 11 cp and you havent punished them for doing infantry only play you kind of deserve to lose. The only fuel purchase I mentioned with the jp4. You don't even need to get it to have good supporting at, and if they're not teching you don't need it at all, you can just rely on shrek raketen and mines. If you get the jp4 though it significantly helps in dealing with enemy armor and stalling the game to get your units more vet and grind it out for the kt.
+1
I play a lot of 3v3 & 4v4 randoms. The most frustrating games are when teammates think that they can spam conscripts until they get IS2's, then get completely wrecked by PIV's, ostwinds, and luchs. The IS2 hits the field about the time that they're getting base-pinned.