In a previous article, Mxsmanic said:
Paul Tomblin writes:

If your FMC wants to descend, ask ATC for a descent. If you're going to
be descending with multiple segments of different descent rates, ask ATC
for "descent at pilots discretion".

OK, thanks. Is that the procedure followed by pilots in the real
world as well?

I live and fly in the real world, so I can only talk about the real world.
My "real world" is part 91 IFR below the oxygen altitudes, however, so
some of what I say isn't applicablle to part 121 in class A airspace.

Another "trick" is to ask for a cruise clearance, which also allows you to
manage your own descent profile. However in my chunk of the real world,
I've never seen it used or needed it.

I fly with a Garmin 296 handheld GPS. In my experience, nearly always
just around the same time it says I need to start my descent if I want to
descend at 500fpm to my destination, ATC clears me down to a lower
altitude without being asked.

--
Paul Tomblin http://blog.xcski.com/
A male pilot is a confused soul who talks about women when he's flying,
and about flying when he's with a woman.