melky and bernie have been fantastic of late. plus, they've had the season (particularly cabrerra) to develop and improve and ... well... season.
sheff and matsui are both basically in spring training mode during playoff season. granted, stat-line to stat-line, the two returning players are better fits for power-hungry yankee lineups. but i can't help but think they are a disruptance to a team at this point.
If Matsui and Sheffield aren't healthy, then it might be a disruptance. Otherwise...you're getting two All-Star veterans with major playoff experience and clubhouse clout. How is that a disruptance? It's not like they're two guys the team acquired at the trade deadline. I'd think it would energize the team to have the familiar faces back in the lineup.
I know everyone loves Bernie. He did a lot of great stuff once upon a time. He's probably a nice guy, too. But he's been hovering somewhere in between "sub-par" and "lousy" for four years, at the plate and certainly in the outfield. Gary Sheffield at 80% is still a significant improvement.