T;
Yes It's mentioned & some actually spent the time to do it in the 50s & 60s.
However; after years experimenting, (hand made parts) the factory keyway(s) were what everyone used as 5,000+/- RPM wasn't high enough to get any real benefits.
With the 'later' engines which are capable of the higher speeds, it became a consideration again and many 'different' grinds have been tried in various timing positions.
Now; If (that word again) your building an engine that has a lot of new ideas/components, YES It's a requirement like you said. Almost all use proven (Pro made) parts though.
The area of experimentation today is with turbos/NOS as camshafts for racing have been "dialed in" @ the MFG test Lab. If a special gear/gears are needed they will sell them with the cam.
If one wants to spend the time on his own fine, but customers won't pay you to 'double check' the cam grinder..
Happy trails.