Excessive AoA is anything beyond CL Max. In the real world when dogfighting we have the ability to pull beyond CL Max for a shot, but although the nose is tracking further as commanded, your lift is actually decreasing exponentially while drag and turn radius is increasing exponentially.
For example lets say CL Max for the F-15 is 30 as you mentioned. If I am fighting you in a 1 circle fight and you are remaining below the CL Max warning tone at 28 AOA while I am flying dead on at 30 AoA, I will outperform your turn radius as I am max performing my aircrafts wing. Likewise if you pulled beyond CL max at 32 AoA although your nose may seem like it is going to come to bear faster you are actually bleeding airspeed and increasing turn radius which will also result in my aircraft getting a shot first.
At the end of the day in the real world CL Max AoA is one of if not the most important number to reference when trying to max perform your aircraft in any situation. It is essential to know in order to employ your aircraft to its max ability vs an adversary. Thus any info on the subject would be great. Same goes for any of the other DCS aircraft.
Leroy