I asked the same thing to a very experienced tech.
He said that generally, on the testastretta heads, if the clearances were set up correctly at the factory, then they are most times still within spec at 7,500 miles (unless it's a track bike or really beaten on).
That being said, my clearances on the horizontal head were all within spec.
The vertical cylinder was all over the place.
I ride with spirit at times, but I don't beat my bike, nor have I tracked this one yet.