Please don't curbstomp me...
I'm writing this at 4:22am on a Sunday, maybe that's why I'm
sticking my neck out like this, but here goes:
I am a very longtime wargamer going back to the 1970's. These
include the well researched monster SPI games like War In Europe(WIE). I
don't know what significance this may have in this discussion, but there
are elements that I think might be appropriate to mention. WIE was so
huge it included every division and independent brigade/regiment of
EVERY nation in europe except the postage stamp countries and
Luxembourg but including Switzerland(It gave you a REAL good idea
why nobody ever took the SWISS on!

).
The reason I write all this is I want people to know that the situation
in the west(for this game anyway) was that the minor powers' refusal
to engage in allied cooperation to defend their countries made the
defeat there a foregone conclusion. However, the POLITICS of the
day, which we in the 21st century see only thru a glass(darkly), demanded
that actions be made by each country involved that were military
madness and only made things easier for the Germans
The Dutch were determined to sit it out as they had in WWI. The
Belgians didn't want a violent conquest by the Germans(WWI again)
AND they had the handicap of a Pro-Fascist King!

Alan Brooke
found out about the nature of the man in their final meeting. For the
French, as previous writers have written, every chance they could get
to advance the battleline forward they would take.
I needed to write all this to make a point about WIE and its'
accuracy vis-a-vis WWII. I am not talking ASB here.
When we were playing this game, we once decided to
do something different to spice the game up. We allowed
a more aggressive Italian war effort so that Malta falls and
logistics and reinforcement in North Africa became easier, and the
Italians are allowed to call back their army and cancel the Sidi
Barani campaign(The Italian army in North Africa doesn't get
curbstomped from the start). Now, in return, FREE DEPLOYMENT
of all combat ready units of the low countries, France, and the
UK. The end result is that when the Germans come in 1940
(the weather rules really don't allow an attack previous to OTL)
everyone is ready and waiting for them in the right positions.
The allies still have all of their unit weaknesses, but even the
Dutch held on long enough to make the Germans pay a serious
price for their actions. What was the result? The French STILL lost,
but not before the Germans exhausted virtually their entire armored
force leaving a very anemic army to invade Russia(They never made
it past Kiev!

). And when did the French surrender? November!
No Battle of Britain...
My point to all this is all they had to do, even without better interwar
preparation, was to get in gear and get the troops where they
belonged, not where the politicians wanted them. But that would
have required a level of leadership that both the military and civilian
command structure of the Allies (including/especially the minors) simply
didn't possess. A poor time for european leadership. After Clemenceau
and before Degaulle.
Thank God we had Churchill(but then he was half-Yankee

).
So, fire away!