I get the feeling there are some "expert tuning" contributors in this thread who haven't even opened a tuning program for one of these trucks...
It is easier to tune a blower on any copperhead OS than it is to optimize camshafts, especially if you want it to drive well. It takes time and patience, the tuner needs to put street miles on it as well as dyno time.
Yeah, I agree... There are indeed a few people who "think" that the old way of tuning is somehow so difficult that more contemporary "tuners" can't get it done. That thought may even be true, but it is the true basics of any internal combustion 4-stroke engine.
It is likely a black art to those who only read about such things rather than having decades of experience in actually doing it ad driving the result. There are only a few basic recommendations for both single and dual-cam setups for best power. If the tuner (even an OEM) wants the engine to have power band characteristics other than for best power, like fuel economy at lower revs, etc. there are still just a few basic settings that work best. No, if you're the spec/dyno number racer, there are many additional steps you can take to get the number you're looking for, but that is just a number on paper rather than an actual result.
The difficulty comes into play when inexperienced "tuners" don't have these basic understandings and believe it to be some black art or magic dust sprinkled on it. A mechanical blower, not an exhaust-driven turbocharger, is quite easy to set up once the engine basics are done. The main variable is the peak cylinder pressure and duration thereof such that the rotating components can handle before breaking. This issue does require experience with the components themselves, not necessarily the specific engine. Well, unless you're taking about some of the older designs that didn't have good basic designs for oiling systems and head porting.
Ahhh, head porting. Now this one indeed requires much more in-depth skill. The basic physics of fluid dynamics applies, but it isn't as simple as the highest air-flow numbers. Oh well, too much rambling on my part...