I can only account for how I do things but everything your "hearing" goes pretty much against everything I'm doing
The kewl thing about this hobby is there is no one way to do things.
This past season I bred the snakes in a fairly well lit room with completely see through tubs sitting on shelves with no hides and have had an awesome season with 8 out of 9 females dropping eggs for me.
My partners have also had the same success doing it the same way I do, I' would never say dark is wrong because it isn't, just different than how I do things.
I also would never say dark is better, I've proven the whole process can be done successfully in fairly well lit up rooms.
Incubation is another aspect of this hobby that has MANY variables.
Our incubator gets plenty of light too and there has been no issues with it either, hatch rates of close to 100%