I just played this with my brother 3 games. Excellent game mode, really fun and dynamic and there is sufficient scale for some interesting strategies.

1937 START

The 1937 January start is not bad; just enough time to spend and equip all starting manpower with infrantry equipment. Unfortunately, you cannot do much more than that... Then it becomes a mind game and micromanagement square off.
If you try develop anything more than a handful of full divisions with artillery, you simply wont have the frontage to match the player who spams 10 width infantry divisions and you will be swamped as soon as the front breaks somewhere; and it will sooner or later because there is not enough soft attack to deplete divisions fast so you can attack ad infinitum.

SOLUTION

However, for the third game me and my bro agreed not to engage in any hostilities until 1938 January. The was started in 1937 but noone made any attacks or air deployment. This was amazing, soo much more time to build up your army, even develop couple of hundred airplanes or a few tank divisions. Sure, you can fort up to 5 your full front but if you do not have the proper army build you will be overrun with tanks.

By 1938 both of us managed to also research militarism and military youth thus vastly increasing our manpower to play with. We had 1,2milion vs a 1 milion army in 1938 as compared to the 1937 situation of max 600k on the field for either side.

THE TEMPO OF OUR GAME

At hostility commencement in 1938 our game was stalemated on the middle with no significant pushes; 70 vs 70 divs. Both of us had tanks and airplanes and parity on the side fronts 40v40 divs both sides. However, we both kept the tanks in reserve uncommited and had a full 24 div army sitting on the middle river lines in reserve.

What finally gave me the advantage was rushing encryption tech. As soon as my brother could no longer tell the ammount of my troops at a particular front I deployed 120k troops from my reserves on the middle river line and 6 elite tank divisions to the south.
In anticipation of this strategic offensive I had spent the last 2 months constantly attacking the intended schwerpunkt both in the north and the south. This was costly but it hid my intention. 100k manpower was lost in softening up the divisions, denying entrenchment bonus, and damaging forts.

Finally, I attacked wtih 6 tanks which were disguised as infantry sprites and broke through after a couple of days of fighting. I counted on my opponents attention being elsewhere and it seems it was (chat banter alluding to something brewing plus army movements and probing attacks on mid might have drawn his attention). The southern flank was overrun, exterminating some 120k men. A whole enemy army in a couple of weeks of encirclements!

I had in the meantime built 5/5 forts on north in case of a counterattack which did not come. Instead, his reserves were deployed south to contain my breakthrough. The front stabilized on the bottleneck before the opening on the south. Since my brother did not counterattack, he consigned himself to a death by attrition because now I had a lead of 10 military factory which was all invested in heavy tanks. Finally, half a year in I made a general attack through the middle with a armored army which his middle could not pierce and my bro capitulated.

Thank you very much for the mod. I wholeheartedly suggest to anyone who plays this to postpone hostilities to 1938 atleast.