required LD versus required MC to make it home ??

You guys need to distinguish two separate uses of the flight
computer.

1. How to use it to maximize speed on the final glide, with an
acceptable small risk of landing out in friendly terrain short of the
airport, costing you only contest points and a few beers for your crew

2. How to use it to gauge safety glides, where speed is not so much an
issue, but making really really sure you make it to the destination is
important.

For 1, Andreas has it exactly right, even at Minden. If you're in a 5
knot thermal, yes, you will do better climbing to the correct height
and blasting home at the 5 knot Mc speed -- if you dare. Try it some
time. It's a lot of fun to let your buddy leave, fly home at 80 knots,
while you climb high, blast home at about 115 and catch him a few
miles from the airport.


For 2, thermal strength is not really an issue. If there were a
thermal of decent strength, you'd take it! The issue is proceeding or
turning back. Here is where you evaluate the wisdom of gliding on with
substantially higher Mc values than the weakest thermal you'd take
(anything!) and substantially higher values than correspond to the
speed you're going to glide back at. Just how much higher should that
MC value (or bugs if you like) be? That depends on just how bad the
terrain is below, and also on the chance of finding significant sink
on the way. Again, smoother air means less risk.

John Cochrane