No Problem...this is actually a good DISCUSSION topic!

IMHO, Crappie and All Fish species in general, are HIGHLY wired into water temps....Water Temps drive the whole underwater ecosystem. Normally every pattern is driven by Temperature. And Yes, like everything else with fishing there are variables like depth, rocks/substrate, water color, bank cover, Downed trees, sun or clouds, fronts, etc.
Temps guide spawning, movement to deep or shallow water, feeding, oxygen needs, cover choices, etc.
If your lake is shallow, it will rise or fall in temperature quickly with wild swings, a deep lake is slower to fluctuate and is normally more stable.....But you also must know what the temps are where the fish are, and most of the time is not on the surface or 2 foot down.

Rocks can heat up and hold heat in shallow water throwing off temps compared to the main lake...fish can spawn in normal substrate that has a lot of shallow rip-rap, steel walls, etc, even though the main lake is not at the temp "We" give as a "guideline" for spawning!
ONE of the main things needed for a successful spawn are STABLE Temps in the range that Crappie like...Again IMHO, if Females are ripe and they have 3 days where the water temp is at 60 degrees at 10 feet deep, and extra heat from surrounding rocks, has the shallows (5 ft and less) a few degrees warmer, then they will drop!
What we see in a few of our lakes is that the BIG Slabs, spawn in PRIME locations in 8-10 feet of water and the smaller fish get the shallow less desirable spots. The smaller fish are normally the last to spawn and they are ravaged by the predators (bream, craws, small fish).

A prime location for Crappie Spawning would be 1 big isolated rock on a hard gravel substrate. This allows the Male to build by the rock, offering protection on the blind side, and easier nest guarding, but yet no places for predators to hide! This is where you see the Largest fish in our area.