"Don't clip the amplifier" is easy to say, and tough to do. Totally
avoiding amplifier clipping under any and all circumstnaces requires
either active power compression control (i.e. "Power Guard") or a
really, really, really big amplifier, the very small signal performance
of which is usually suspect unless the amplifier is made extremely
heavy and hot and has a very high quiescent power draw. A 20 watt tube
amp that pulls 50 watts at full power is more efficient in practice
than a 250 watt solid state amp that pulls 80 watts quiescent and 500
at full power if either provides the same _subjective_ performance-even
though the solid state amp is more efficent for each watt it puts out.

I guess it depends on what you are doing with the amplifier. In a live venue
or a recording studio, where you have no idea in advance of what the signal
levels are going to be, I would agree with you.

At home, level matching everything from the CD player to the volume control
guarantees that my power amp will not clip until the preamp is turned up at
least 1/2 way. That setting is well above my comfort level.