Are USCF regular ratings more accurate than quick or blitz ratings in regards to quick or blitz games? I recently went to a USCF tournament. Although it was quick/blitz rated, regular ratings were used for the purposes of pairings and prizes.

This led me to wonder: are regular ratings actually better predictors of results in quick/blitz games than the quick/blitz ratings themselves are?
Probably not technically if everyone played a lot of rapid games, however, I have seen organizers do this before since the regular ratings usually have a more established basis. In other words, because people have usually played a lot more standard rated games, in that respect, they are more accurate. It helps prevent sandbagging.

In reality, in rapid and blitz, a better predictor is probably age. Kids often perform better than their standard rating the faster the game. I once won an under-1800 blitz tournament when I was an under-rated 1100-player (I went up to 1254 after the main tournament). I was about 18, and the mind was very quick back then (there also were not a lot of kids like there are today).