Did some web searching and came up with zero hard data. Lots of opinions; no data.
Most people seem to agree that it's all about sealing the rings. Few agree on how to properly accomplish that.
Based on the stories I read, it doesn't make a whole lot of difference with a decent, modern engine. Found several stories of people that took their cars from the showroom to the drag strip with no apparent problems. I wouldn't recommend doing that but it doesn't seem to be a big no-no nowadays.
YMMV
At least with oil, one can find UOAs and such to back up claims.
