I recall that once when doing a spiral dive recovery in a PA28, as part of an IMC revalidation, I accidently managed to wack the throttle fully open as I went to grab it with the intention of closing it. There then followed a second or two of both instructor and I reaching to close it before I pulled hands off and let him deal with it. No idea what speed we were doing at that point, but I know the instructor said afterwards that we got pretty close to VNE. All pretty stupid and nasty really
I failed the test and had to do it again the following week.