Jeffers was never the brightest was he, he's made lots of bad decisions. But for a while there, we did genuinely have a potential superstar. Rooney coming along so soon after distorts it a little, but he was a freak.
Jeffers was still a really good player though, quick, intelligent (football wise, not so much off the pitch), and a good eye for goal. I've said it before, but the ego alone, moving to Arsenal THEN, thinking he'd get a game ahead of Henry, Bergkamp, Wiltord, Kanu... Insane.
Like Kenny in many ways, the fame did him, and he couldn't cope, and wasn't grounded/intelligent enough to take advice. If he hadn't moved, he could've been a legend, but instead he was basically finished by the age of 23.
In some alternate universe, there will have been a resurgent Everton at the turn of the century, captained by a talismanic 29 year old Billy Kenny, with a free scoring 21 year old Jeffers leading the line, and a young 16 year old prodigy called Wayne Rooney breaking in to the team to play alongside him.
Ah well.