Instruments- discuss specific features, luthiers, instrument problems & questions
Well, first, it shows that McSpadden does not understand the art of lutherie. The bridge is not compensated, the saddle is compensated,..., and no, it doesn't change just because you are making a dulcimer.
That aside, because of the difference in gauge of strings, thicker strings tend to become sharp as you play higher and higher frets. To adjust for this, the saddle is angled so that the distance from nut to saddle (bridge) is greater for the thicker strings. Longer distances tend to produce lower notes. This keeps the thicker strings from becoming sharp as you play up the scale.
In the guitar world, a compensated saddle will not only be angled, but frequently has recesses carved into the saddle itself.
A compensated saddle does not prevent a musician from playing DAA. Simply string the instrument with a thinner melody string, maybe a nine, and a thicker middle string, maybe a 12 or 14. Works just fine.