It was recommended by some pistol smiths when you got your new comp gun, (Wilson, Pachemyer, Clark) before IPSC was taken over by the gamers.
Just so everyone else who's reading doesn't get the wrong impression, what you described would get you immediately disqualified from a USPSA match.
Rule 10.5.9 (Match Disqualifications)
Failure to keep the finger outside the trigger guard during loading, reloading, or unloading.
