Once you know what the cold setting is, I see no reason why you can't check them on a cold engine and re-adjust to that cold setting again. The temperature variance on a cold engine would be the difference in atmospheric temperatures, say from 65 to 85 or 90 degrees. With a hot engine is it always going to be ran up to the same temperature?Then when you start checking, you could have some cooldown before you have finished, which could allow for some variance. I ran supercharged engines in modified pulling trucks for 25 years, and always adjusted my valves cold.In all that time ,I can't say that I ever had breakage because of improper valve settings.
