I also have the small HF variable speed grinder. After I cut and grind a tungsten on the diamond wheel, I polish it on the scotchbrite wheel of the small grinder.
What I've found is that depending upon the application, it often matters less about the quality of the finished grind then it does the angle. A sharper angle with a sharp point focuses the arc tighter and a longer angle tends to make a wider arc that moves up the tungsten in a short period of time. I don't even like it like that for Aluminum where a wider flame is often preferred.
I think if you're doing very fine and delicate work then it pays to go to extremes other wise just following the basic best practices seems to be enough.
I can't count the times recently where I've burnt through my last tungsten and just sharpened it on the fly (so to speak) and finished the job without issues.
Steve
Miller 212
Everlast 250EX
Everlast PowerPlasma 60
Victor O/A
Current Project: 21' Jet Sled Rat Boat.