I just tapped 8 more blind M3 holes and 8 more M4 through holes using the dewalt cordless adjustable speed with clutch and I've just gotta say, I can't really see the point of using a hand chuck if you have one of these. (and who the hell doesn't these days?)
With the clutch set to 1 (the lowest setting), you can basically floor the trigger without breaking the bit or the threads. It's practically idiot proof. In some, out some, in some, out some... in some, all the way out... Zero issue.. and I can't see why I'd ever want to use a hand tap for this.
Having 2 cordless, variable speed drills, with clutch, is so handy regardless so you don't have to switch bits as often. Yellow drill holds the drill bit, then blue drill holds the tap! (or even better, drilling with a drill press..)