Drag car -
Pretty much in my line of sight, and I know the needle position without directly looking.
Plus a shift light in its face for further idiot-proofing.
I'll peek in the water (6000 max).
I rarely bother at the stripe, though, unless T&T.
Shutdown I'll glance at temp & oil PSI, but have another idiot light for oil PSI.

Road course car -
I'll glance on the straights at a gear change or two, along with temp & oil PSI, rest of the time it's the Zen method.

But yeah, with seat time you do learn to judge the sound.