The angle of the trench is different than valve angle. milling it deeper should help as it goes deeper it is moving the shaft towards the intake. May need to run longer valves also.
It will help but is really only a slightly better bandaid, as it causes (what I believe) to be extra loading at the adjuster/pushrod interface. Just make sure you have good rockers with good pushrods and the right spring for the job. J.Rob