384%! I feel violated.
This is by no means the best, in fact as far as uber research planets go this one is fairly ordinary, it's just a screenshot I've happened to keep around. I think the record was somewhere around 20K RP's per turn for a single planet, although that's as much a function of how many research resources you have to mine as well as the precise planet location as well as bonus tiles among other factors.
No research co-ordinator (+25% = equivalent of 7 neutrality learning centres)?
No Research Coordinator in DL.
I think I'd cry if I built all those starbases and they got destroyed.
Basically once you built something like this and could to afford to set your sliders to max research you could quickly out research any and all AI's and be in a position to wipe them out with your superior technology.
Just one of many ways to win. Back in the day it was a pretty popular method, however it's long since been supplanted by more efficient methods.