Stuff
True once upon a time, not really anymore. OKW's late game advantage has been hernangled to pretty much be on par with Ostheer/Soviets (USF still suffers but with good micro can do fine) since Relic realized a faction that auto wins after a certain time period is dumb just like Necrons and IG were in Dark Crusade.
Vet 4 and 5 on OKW units outside of Volks is quite rare, and you will always have less vehicles than your enemy does assuming equal map control. The reason why OKW appears to do so well late game is they don't need to micro nearly as many units as other factions do, but the investment in those units are so huge. Losing multiple vetted squads or a Panther can easily be GG for OKW in 1's and 2's.