Saving manpower is good too
yeah its decisive,
i guess the real key is in the appropriate size of forces, first (globaly, all types)...
but mainly good use from to limit losses of MP.
also, of course, obtain all events giving u MP is absolutly necessary too (there are 900or1000MP to have from 1938to1941, if i remember well...?)
its absolutly necessary to have them all with Germany.
and also necessary to do geopolitical choices aiming MP gifts such as u aim main real purposes, etc...
there are other tricks (good management, good choices, etc, etc)
but, on long period of time (some years of war, all fronts concerned), the real economy of MP comes from good use of troops, i think.
even with very effective strategies and managing,
if u use infantry (and all light troops. opposed to all armored troops, i mean) to attack, the cost in MP is just simply enormous (even with brilliant and expected victory).
so, its necessary to use them well and limit (more as possible) light troops use for defense, hold passive frontzones, support -only !- attacks (when necessary), act with IF no other choices, etc...
and really foccus on armored troops to strike hard and make strong attacks.
in offensives, cost in MP with armored troops can be about 10to20 times less important (it varies, depend of many contexts/datas, of course)
but if u use properly armored troops to strike more often u can and light troops to defend, it can works.

(till end of game)
...coz, on long term, it really counts (more than any other aspects around MPs) ! (y)
of course, it must not be "strict". (such then u resign occasional/tactical/operationnal effectivness, i mean... thats unsain, more than expensive victories)
priority stay to prevail in battles, thats clear...
but use correct troops for correct use (and though it
BEFORE -no impro !- with good preparation of each wars/offensives. rightfull troops in rightfull positions before engage the offensive, etc, etc) is clearly necessary...
its best way to economize MP and hold longer with Germany, i think... (more than any other way) (y)
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