The dry burn does just that, it burns off sticky, hard and atomizer-killing
e-liquid residue on and near the coil. Burn anything, and the resulting effect is it tastes and smells burnt.
The only way to remove the burnt taste is to remove the burnt material.
That's why I like using an ultrasound cleaner before and after the dry burn. Before to remove what can be "blasted" off the atomizer and after to remove the burnt residue, nixing the burnt taste due to the dry burn.
Also, since switching from commercial to DIY e-
juice, I get almost no burnt taste even without cleaning after a dry burn. Something is in commercial liquids I've bought that builds up on the coil, whereas VG, PG, PGA and a few drops of flavor are leaving almost nothing.