That's pretty true Blue Yoshi. At least I've noticed that also; if I 4/5 stock a player on kaillera, I'll try using falcon or samus, who I literally never use, and then the game becomes close, but still with a slight edge for me. It all comes down to the basics like cancelling, prediction, accuracy, etc. If the player is that much below your level, chances are you can kill them with any character. Like Koro said, the skill gaps are huge in ssb 64. That's why this game rox all your pairs of sox.
Btw, what does the term "sandbagging" mean? Seen it used a million times on here and have just ignored it. Thanks.