Open tunings seem totally logicalsomeone somewhere picked up a guitar and, not knowing any better, simply tuned it to an open chord and started to strum. Chords seemed no problem either, just use your extended finger to bar across, or better still, find an old piece of plumbing or Grandpa's sparkplug socket and use that as a bar. So the slide was born, although those pesky now marker-only frets got in the way - soooooo - let's jack up the strings to clear them.
And thus were a lot of good guitars condemned to a torturous deathironically, the finer, delicate instruments would suffer more than the plywood dime-store ones. Normal guitars simply aren't built to withstand the multiplied loads that jacked-up strings exert.
Enter the acoustic-electric slide guitar. This instrument was conceived, designed and built as a slide guitar. The differences are criticalcompressive bracing that can resist the high string loads, a wide and high bridge producing normal down bearing on the nut, a similar raised headstock to lower the bearing on the nut and eliminate string creep, a constant-profiled neck that does not require capo adjustments, and the visual signature of two mirror ebony Pickguards that also form the rim of the sound-hole to guard against top-wood tear-out from fingerpicks. A pot knob also protrudes through each Pickguard; the volume on the treble, tone on the bass. The BIG question was: would a magnetic pickup sense the strings some 3/8" above it?
Oh yes, no problemo. These things go like stink.