Don't agree.
I've seen some teams put out what they would consider not their strongest eleven, and have been found wanting. Newcastle, West Ham, Southampton, Aston Villa, Palace et al do not have two strong XIs. In fact, some of their back-ups are awful.
Button
Burn
Webster
Dunk
Veltman...
We are less relegation fodder now than at any time in our recent history in the Premier League.
And we've only ever spent one week in the bottom three in that time.