If we're talking hydraulics for street/strip. I surely wouldn't do it. Once they're adjusted there is no more adjustments needed as with a solid lifter motor. It's less work just to wipe off any oil if does run down. One can always position rags against head for spillage while adjusting. I lay valve cover on side I'm not doing until I get there and then cover the side I just did. If worse comes to worst. You can always shut motor down for a spell to let oil drain back down before other side is attempted. This is the way I do it and just my opinion on the matter. As the saying goes: Opinions and a--holes, we all have them..
