My two cents is because during WW2, Assaults and Attacks are typically heavily planned days ahead of time. Higher headquarter support units are allocated and special resources dedicated to the Attack/Assault force. Those things take time.
A Probe is more of a hasty attack or a reconnaissance in force against enemy forces discovered during forward movements. They develop too quickly for that kind of operational planning.
[For the record, I also opine that any forces defending against an Assault/Attack should also be allowed plenty of TRP's and pre-planned protective fires but that's a separate argument.]
I can understand your point of view about the Probes but in CM I would think that some probes may be covered by off board mortar fire.
And this makes me think of the question of "what is the definition of a Probe in CM"?
In CM, it seems to me, that it is really an attack with objectives that are closer to the jump off point than an Attack or Assault. Since the distance is shorter the attacker is given a smaller ratio of attacker/defender of 1.5 to 1.
It's not even limited to size. A probe could be any size. What if it's a huge probe of a battalion size on a huge map?
It's not like a Probe in CM is just go out and see whats what or knock out a target, come back, and report to HQ what you saw.
I do agree with you Badger that this is what a probe should be.
I suppose you could design a scenario where you just have to touch a VL or destroy an objective or both (which isn't a bad idea by the way) but all the QB Probe maps have Terrain Objectives you need to take and hold.
Also, especially later in the war, I believe American mortar and even 105's could be available and called on very short notice.
In fact, this is a good question for a discussion. I think I'll post this on the general forum and hear what others think.