Yup, it's just a tap. The difference is that it doesn't cut. You drill the hole a little bigger than a cut thread. It's tapered and it 'pushes' the material into a thread shape--the low spots flow into the high spots.
I thought they would take a lot of force before running it, but wasn't sure. I tried two identical taps from the same manufacturer.
The 'cutting' tap went ok through most of the hole then jammed (normal chip binding). When I tried to back it out, it locked against the curled chips. It took a little wiggling to get it loose. That's nothing new--been doing it for years.
The forming tap just took a steady torque. It never got harder or easier. Once the thread starts 'forming', the force remains constant. It felt about the same as a tight nylock nut.
I ran 4 parts with two holes each. Painless.
20 more parts to go.