Its fun to work on this stuff, and i would probably do the same, but in all reality, there is no reason to touch those valves.
Its such a strange thing, but when you see the number 2 intake at .15, its good, and thats about it. It sounds like it should be a warning, but you cant interpet this info like that. Odds are very good that in another 25,000 miles it would stay right where its at. That valve was probably at .15 at 3000 miles.
Thats why those go/no go gauges are awesome because its all the into a person needs. If you ever have to repeatedly adjust a valves clearance, its game over.
Maybe a better way of saying it is that valve thats at .15 is not going to move to .14...then to .13. ..then to .12. If it was doing that, you would have never saw 4000 miles.
And for fuck sake, if you adjust, dont do that dumb thing of aiming for the middle. These tighten unless someone fucked up the base measurement. Shoot for the upper end of loose.