Jeff,
I did make a comment on this. It's common and done all the time.
If you're in a shop building "race engines", you have the engine on a stand, no car, and no way to install and run the engine. These would be the conditions where one would set the valve lash with a non-running procedure.
If you are in a working automotive shop where the customer is paying $75 dollars a hour and he drives the car into the stall, you would adjust them with the engine running.
If you adjust them running on a regular basis, handling the stubby screwdriver, end wrench and feeler gauge would become habit. It's difficult to be proficient at something when you never do it, but that doesn't mean you need to brand the gentleman that does it the "other" way a fool or a shade-tree mechanic.
Stuart
