Hmmm. I had not heard that a glider would not stall while in a slip, only that if it did, it would spin in the opposite direction, presumably giving you slightly more time to recover. I regularly slip my ASW 24 on final and have always been careful to keep the speed up, even though I suspect the ASI is not as reliable as the slip angle increases.

I recall that at least one ASW 12 pilot from the old days had two ASIs installed, one for normal flying and the other with a pitot tube bent out at an angle that he used to monitor airspeed when in the dramatic slip that experienced '12 drivers used to get that ship down in a hurry sans tail chute.

Chip Bearden