I agree that higher MacCready settings are safer. I have found that many
glider pilot find that point difficult to get their heads around - probably
because using a higher MC causes your glide computer to show that you need
more altitude, and because you will be flying faster (which seems less
conservative) if you follow the speed director.

I was flying a contest last year and made the bone-headed error of
increasing my MC when I hit bad sink on final glide. I don't recall if
it was nerves, fatigue, or what, but during the last 12-15 miles
across the tiger terrain west of Turf, the sink got worse and worse,
and instead of reducing my MC, I increased it.

Of course, that would have been the proper action during my last
climb, but I got my wires crossed when the vario turned into a
divining rod after I passed up the last landing option. I ended up
doing a rolling finish, and being most thankful that the mistake did
not damage anything beyond my ego!

~ted/2NO