180 Too Fower
I don't think your example is quite correct. Judging by his name I think omni is refering to B737s. If so I think the max 20kts is over and above Vref only. So in your example the VApp would be limited to Vref +20.
I could be wrong though, I've been on the Bus for a couple of years now. Incidentally the Airbus has groundspeedmini, this is a black art which can only be devined by wizards and mages.