Darcy does get a bad rap here, considering 90%+ of his tenure was as an internal cap team - at best.
People forget Darcy early on tweaked his inherited, over-achieving (yet entertaining) roster and got to the Finals in 2 years. Just via trades (and discounting rentals like Juneau, Gilmour, et al):
In: Jason Woolley, Geoff Sanderson, Stu Barnes, Rhett Warrener, Chris Gratton
Out: Pat LaFontaine, Brad May, Jason Dawe (made room for Varada), Donald Audette, Matt Barnaby, Derek Plante, Mike Wilson.
Then still being very competitive the next 2 years.
In: J.P. Dumont, Steve Heinze, Donald Audette (again)
Out: Michael Grosek
Then the first spin-out, as Peca's holdout and Hasek's wanting out blew up that roster. We know what came back - Pyatt, Connolly, Kozlov. That was all pretty much externally forced.
So, in 2002, rebuild 1 commences.
In: Jochen Hecht, Adam Mair, Danny Briere, Chris Drury, Mike Grier, Toni Lydman
Out: Gratton, Varada, Kozlov, Woolley, Varada, Rob Ray, Erik Bustmuffin, Warrener, Curtis Brown
That post-lockout team will rank as good as any Sabres team until they do win the Cup.
Then of course, Rigas/Golisano/Quinn blew that all up. This is when the stripdown should have started, but in those days playoff gates made the difference between viability and ... who knows what. So when you had to sell, i.e. Campbell, you sold. But there were rentals too, to try to get to the playoffs, and maybe steal a round (i.e. Zubrus). Those were the floundering, mediocre years.