The highest advertised duration cam that Summit shows for a SBC has 346 degrees of duration. Unless you have a custom cam that has more than 360 degrees of duration, it works.
Well...advertised duration plus clearance ramps, although the clearance ramps are not
hugely important. I mean, even if you're adding only .025 preload, what difference does .006 of clearance-ramp make? The preload WOULD vary by up to .006. (The engine won't know the difference.)
It would be really hard to find a hydraulic cam where that preload adjustment method WOULDN'T work. But I'll acknowledge the possibility that there could be some, somewhere. Folks buying such a cam...have probably got considerable experience setting lifter preload.
I've only ever installed 4 cams and didn't degree any of them. I've seen it done once, on youtube, and read about it in a book specifically for Pontiacs. Never did it myself, though, because well I don't have tools and it's not a big deal to me.
It has the potential to be a big deal to the engine, though.
Degreeing cams assures that all the various machining operations related to camshaft--crankshaft synchronization were either done properly, or they were accounted-for by offset keyways, offset keys, offset bushings, or whatever method was used to correct the cam--crank phasing.
For the record, the Vortec short-block I bought to re-engine my '88 K1500 got rings 'n' bearings, cylinders honed, seals and gaskets. I re-used most of the pistons, sleeved one cylinder, re-used the cam and timing set. The cam degreed-in within one degree of "perfect" even with a used timing set with unknown miles. The point is, I know the cam is where it's supposed to be. If the engine ran goofy when I was done, I know I
don't have to dick with the cam timing to make it run "right". Also important on a genuine Vortec installation (which mine is not) if the cam sensor signal doesn't synch with the crank sensor signal, (P1345) I know that it's a matter of the distributor position--not the cam timing itself.