I am thinking that that business about a "sixteenth of an inch above the strings" may be counter productive advice--

You can move your fingers downward more quickly, nimbly and with more force than you can move them up--too close to the fretboard will require you to move the fingers up before coming down on another fret or another string--At any rate, fretting the strings is not as critical for speed as sounding the strings, which you do with the other hand entirely--