After set up when both sides know where most pieces are guys still try to hide their leaders at the bottom of the stack while the stack is in clear LOS of the enemy. This is a bush league play that just slows the game down...
Steve
So hiding the HMG, FT, Psk, etc under a leader is OK? Or hiding the 8-3-8 under that 8-0 leader is OK?
My point being, why wouldn't you look through all the visible (un-?) stacks anyway in order to see, not just leaders, but "big" hitter SW's, quality of units, quantity of units, type of units, etc.
Or, here's a thought...just ask your opponent what's in the visible (un-?) stack? If your opponent refuses to give you such a stacks contents then, by all means, man-handle the hell out of said stack.
Only one counter can be on top...so if it isn't the leader, you are assigning some malicious intent ("hiding") to your opponent. Problem with that is, per rule, it's a false narrative. Your opponent can't "hide" counters in a visible (un-?) stack.