Keeping with the catalogue fails once users have more than one catalogue, so that option is really only for when you carry round your catalogue in an external drive like a colostomy bag. But yes, it shouldn't be hidden and I find my method very practical.
Wait, if I have more than one catalog, LR is going to save each group of presets with the catalog right? Not an issue IF all the catalogs are accessible which of course they must be. Keeping all this in sync is messy.
But, if you have 5 catalogs and the settings are on the boot disk, all 5 have access to the presets in that
one location but
nowhere else. All 5 have no access to presets if the catalog moves from that machine. Two bad situations.
Adobe has it right with DNG with respect to embedding lots of useful stuff in the container. But the presets, lens profiles, DNG profiles (outside a DNG file use) are scattered all over and on the boot disk. Bad situation.