There was also a section about Lightning:
Is GFCI tripping caused by electrical storms normal ? Are my GFCI breakers too sensitive ? Is there any way to modify the circuits to avoid this?"
This doesn't surprise me. Long runs of cable will be sensitive to the EM fields created by nearby lightning strikes. Those cables probably have 3 parallel wires: H, N, G. The lightning will induce currents in all three which would normally not be a problem as long as H and N are equal. However, I can see this not being the case since there will be switches in the Hot but not the Neutral so currents could easily unbalance.
For the record, I am not endorsing the above comments, only pointing out that they were there.
I have no reason to disbelieve the claims or "theories" of nuisance tripping. Isn't a Refrigerator a Grounded Appliance and should therefore trip a breaker if the frame becomes energized? Why the argument about removing it from the GFCI?
From working in the field I have seen many times where a GFCI has tripped for no apparent reason at the same time as a Lightning storm or during some unusual power event. Take that as you wish. If you want to ignore what seems to be the general consensus that's up to you. I would suggest that you start a topic under the Theory section if you want to delve into it further.