Why? You seem to miss the point completly. I don't have pkgconfig. I don't want pkgconfig, so why should I read up on it? I have been building software from source for a few decades now. Since usenet was the way to distribute the sources for most. The all the worlds linux folks are as annoying today as the all the worlds a vax foks where then.
If you have been building software for that long, it should have taught you that building complex software with many dependencies without an unified system for discovering library paths, compile, link flags etc. (which is exactly what pkg-config is) is a living hell of hooking up each and every library to the build system via crappy third-party autotools macros for which no decent unified and maintained archive exists. And in this particular instance, these macros were even unable to resolve version requirements for which reason (I guess) they were finally nuked in favor of pkg-config.
It could be that your system doesn't ship pkg-config (which I would doubt, unless it's Windows), but since you've been building software since vax days, it would certainly take you near-zero effort to build pkg-config in addition to cgminer. I bet there are even third-party repositories with pre-build binaries somewhere around.
The point is I don't want to install pkg-config. I know exactly where say libcurl is, as I of course build and install that from source. If there is another dependency I would do the same. At least with makefiles I could also just edit them easily myself quickly. Autotools already makes that a longer cycle to fix when things go wrong. What does it hurt to at least give the option for me to tell it exactly where to get the library it wants to link to? Put in the README/INSTALL the version dependencies (though the library itself should offer some way to check this, and let it abort if it is a bad version).
What is wrong with leaving in the manual override option? What is crappy about leaving people the option to not install more abstraction layers on things they don't want? If I want enough abstraction layers I may as well just go use windows and autoupdates.