Tex, although I certainly know you're not a moron(!),
there are plenty of examples of even cassette multi-tracks
providing GOOD ENOUGH sound quality for commercial releases.
While objectively the sound quality of digital is better in the
"technical" sense, sometimes due to a song's vibe, etc.,
a warmer lo-fi technology like cassette can be more effective.
Examples would include Springsteen's "Nebraska" (needed mucho
mastering though!), Guided By Voices' various releases, etc.
In addition, as you may know, the layout of a portastudio is more
immediately intuitive than scrolling through menus on a computer,
or a "studio in a box"-although the Tascam 788 seems pretty easy.
BTW, the early Tascam portastudios like the 238 (8 track) are
generally considered superior to the present model 488.
The trick is to find one with either low use or well maintained.
If you can find one with dolby that's supposed to be better than
the dbx noise reduction-model 238S, they don't come up for sale
too often though at e-bay!
P.S. I hope Pirate's comment was just missing the smiley face
icon!