Kanna's Kishin Skoukan Spawn Increase

Any mob spawner can have a cooldown timer associated with it - separately from the interval between spawns, it won't spawn a mob before the time is up.

There is a lot of truth to what you are saying and the base of it is supported by the behavior of LHC. It was part of my initial theory, but I can tell you why I didn't pursue it:
LHC - Crockies - with 1-3 people on the map, the spawn limit is 4. We know there over a dozen spawn points on the map. When Kanna activated her skill, the spawn went from 4 to 6, all instant. With a 4th person on the map, the spawn changes to base 5 and the Kanna spawn increased to 8, again, all instant.

LHC - Castle Golems - Same spawn pattern as Crockies (starts with 4). There are only about 6-7 spawn points on the map, though. (Very Tall Walls 1, I believe. It's the small map.) When Kanna cast her skill, the spawn max increased to 6 (from 4), however, it wasn't instant. I would get 4 or 5 mobs to spawn at a time, but not all 6. The most it would give me was 6 on a map, but only 4 specific points would spawn -every- tick. Three other points would only spawn every -other- tick, or so. (This goes back to similar behavior I noticed when training on a glitched version of this map a couple of years ago. The spawn would max at 9 golems, but a maxiumum of 5 would show up per tick.) This tells me that this map has some normal delay spawn locations and some longer delay spawn locations. Kanna's skill did NOT speed up the long delay locations, but it did increase the mob limit.

Thanks for bringing up this scenario, Stereo.