As long as everyone is clear that those aren't "HIS" techniques but rather a little bit from several other equipment guys that he's put together. Well, I take that back, the shimming of print heads with various household items is his, as well as one of the more absurd methods I won't go into detail about, you'll figure it out. But most press owners shouldn't need to worry about shimming print heads. That's one reason why we have adjustable screen holders, to make up for any slight need for calibration among the print heads, among other reasons but I digress. But to my knowledge, there was only one manufacturer that had any severe issues with print heads being out of an acceptable tolerance level.
It should take a few hours to do this, and I know it took the better part of a day and a half for him to calibrate a few 16 color machines using those techniques he describes in his videos. I've calibrated our press about every way it can be done, and I think the best way is to use a flood bar on a baseline print head (find one that is in between the highest and lowest), then get a baseline pallet the way Winston said making sure you have room to go up and down if you need to. Then bring all your pallets to the baseline pallet's specs, then go through all the print heads to match your pallets.
I can't stress enough how important it is to have pallets within a respectable tolerance. I used to think that tolerance was very tight, but over the years I've relaxed my stance on that opinion and if your pallets are within 1/32" from one another you'll be within an acceptable range to see great setup speeds. I've got our pallets within 1/100" using dial indicators mounted to a flood bar, actually it was tighter than that, and I can say that we haven't seen any loss in setup times now that they've been knocked out to within 1/32" and 1/64" where they are now. A big reason for not needing such a high tolerance is we aren't using 50 newton screens any longer and 25 newton S thread screens are a perfect compromise in our shop since it doesn't rely on an super calibrated press.