Partly so. Both can cause interference issues, which must be checked every time components of the valvetrain or piton are changed. A high lift rocker may benefit from retarding the cam 2° to 3°. This would increase valve to piston clearance, but the only way to know what the engine wants is to test on a dyno. On a solid lifter combination, tightening or loosening valve lash by 0.002" may be required.