Well, reading the link, it appears that they turned it back on because it was impossible to trim manually.
Pitch (& roll) trim are independent of the MCAS. The problem is, with the MCAS engaged, available pitch trim is very limited. I wasn't in the cockpit so we really won't know until the full report comes out AND vetted by the FAA and Boeing, but ostensibly, with pitch trim disconnected, you can manually trim with the big trim wheels on the side of the throttle quadrant. The huge turd in the punch bowl with MCAS, if you wait too long and the system (MCAS) has trimmed nose down and at low altitude, you're screwed (From what I saw nose down pitch was at 6 degrees which is YUGE and your trim tab only gives you ~1 degree. In the airplane I flew pitch trim was electric only, so it the pitch trim failed, you could still fly the jet with no issues, although coming aboard, could get a bit sporty. Suffice it to sa, if they kept turning it back on and every time it came on it kept trimming nose down, well we know the rest.
