I try, try I say, not to break much more than 700' or 800' agl on any leg, at least until I get on approach, then up to 1200'AGL. Makes for a really, um, interesting flight at M0.98 or so in an F-111.
When I was in my avionics school, AFTA, in Millington Tenn, many many years ago, they showed us a film about the F-111 Terrain Following Radar system. Some pilots tried to set it on a fairly "firm" setting, which determines how closely the plane follows the terrain, but they got so beat up, banging up and down over every tiny little bump, hard and fast, that they wouldn't be able to fly for a while. Strap marks all over their bodies, or banging their heads off the canopy, even the seat-cushion seemed to turn solid, they'd say. After showing everyone how tough they weren't, they would never set the system past about 50% firmness.
I haven't tried that system yet. I only hand-fly the plane. Maybe after the race
I value what's left of my old, tired bod!
Pat☺