They could REALLY get it right if they:
A. Adjust the denial window to create more reactionary block of grapple advancements. or leave it alone if they do B.
B. Add in a pre-block input for SOME positions in addition to the reactionary denial windows. Similar to how THQ allowed for directional transition denials to be held. If I want to prevent a pass from bottom side control to Full Mount. I can try to time my reaction like we do today, which is risky, but could also lead to a reversal.
OR I should be able to hold a transition block to account for that specific pass in advance. An Animation would play out on screen of my fighter raising its leg to create a barrier for the pass. This of course could be broken down, similar to how strike blocking is broken down in UFC 3. If I throw enough GnP from Side Control, the pre-block breaks down and my leg animation goes down.
This will allow for more strategy as well. I could see the prevent animation on screen as the top guy and either go for the break by landing GnP. or I could take the open path to North South.
As the bottom guy, I may have successfully baited the top guy into getting reversed from the transition to North South, or at minimum, kept him from getting mount, which is way too easy to achieve now.
This same concept could be apply to various positions, likely not all.
Havent really thought about it too much..so Im sure its flawed but the concept is appealing to me.