I think the Hellcat originally caught the Japanese by surprise. They had developed tactics for use against the Wildcat. When they tried them against the Hellcat they did not work.
Amazing thing is, even as propellor driven aircraft go, the Hellcat was thought to be growing obsolete as the Pacific war proceeded, and was slated to be replaced by the F8 Bearcat before the war abruptly was ended by the A-Bomb.