it is for OOB!
i don´t know if it works in global, too, but in europe 1940 it worked quite well. maybe you can call it full-scale-barbarossa: i bought from the first round on only mech and tanks. an occasional sub to deny the no-sub-NO, but mostly mech.
G1: 6 mech, 1 sub (30 IPC)
G2: 1 inf, 2 art, 3 tank, 8 mech (61 IPC)
G3: 3 inf, 13 mech
attack on G4 with a can-opener by italy in east poland to land mostly all german aircraft there. mass all troops there, too. conquer karelia, vyborg, baltic-states and bessarabia.
the subsequent rounds your buys should cover actual situations, which means paying more attention to the uk und the usa, of course. But, mostly buying mech is helping a lot. i can only speak for myself so far, but i had been amazed by the cumulative power of a mostly-mech-buy sake of speeding up the german play by faster troops as mech an tanks in combination with fighter and tactical bombers.
russia gets under higher pressure and needs to give up certain territories to secure defense. Novogorod fell in G5 without problems, but italy has to make sure to clean up the baltic-states, which means mech-buys for italy, too.
even, if the allies start to harass germany on the continent, you can cover a vast territory with mech-supported-forces for defensive and offensive purposes.
this said, it is really worth 4 IPCs! :D
i hope it helped you a bit.
rock`n roll