I used to change oil and check lash each day, it got less and less each year and this last year I didn't change the oil and only checked the lash twice. The second time was only because I had half the rockers off to replace the broken one.

The sound of the valvetrain when we arrive at our hotel usually determines a lash check or not. I have learned after hours at 3500RPM and engine temps sometimes over 200 that it sounds like it has 1/4" of lash but when you check the next morning it is fine.