Bod gurgled happily, sounding much like they were
saying:

If none of the other responses works, try CPU-Z.
http://www.cpuid.com/softwares/cpu-z.html

Use this first! It's excellent. It's now in my set of software that
I install as standard.

I agree, it is very good.

I can honestly say I've never had a need for any of that information
- or even cared particularly about the clock speed. Either the
machine's quick enough, or it isn't. If it isn't, it's rarely the CPU
speed which is the biggest bottleneck.

So what am I missing?

The information.

Well, yes, but is it information, or just data? Why should I care?

Handy to identify not only your CPU info, but type of memory
installed/Graphics card etc, all in one place. Obviously wasted on you.

Yes, it clearly is. That's why I'm asking - because I would like to know
whether there's something I'm missing.

Unless you're producing some benchmarking, to produce quantifiable
performance stats for comparison purposes, I can think of no reason you
would need to know - other than purely for interest's sake.