I don't know if I'm qualified but I have learned a few things the hard way!
I believe I've stressed fish with too much winter aeration but it's never caused me a complete winterkill or even close to it. My biggest pond is about 1/2 acre for whatever that is worth.
One thing to keep in mind is 99 percent of all fish kills are due to a lack of oxygen. So logically aeration, even too much, would not eliminate oxygen.
In most cases where you have a complete winter kill or almost complete winter kill, D.O. levels dropped to critical low levels due to one, some, or all of the below:
1.) Significant snow cover for an extended period of time, which blocked out oxygen production via photosynthesis. Usually the shallower ponds are more at danger as they have less of a reserve of oxygen saturated oxygen just before ice up. If there is no photosynthesis and significant snow cover it's only a matter of time before that reserve gets used up.
2.) A pond that has had a build up of sediments and decomposed matter for a period of several years or longer with either insufficient break up of the stratification, or no break up of stratification at all via a bottom diffuser(s). (During summer stratification.) This results in anerobic decomposition on the bottom vs. aerobic which creates toxic gases like hydrogen sulfide, and of course ends up using oxygen under the ice.
3.) Extensive macrophytes going into winter that die and use up oxygen as they decompose under the darkness of snow cover.
4.) Too many fish could use up oxygen faster with the above conditions, but it's only speculation on my part.
