On Friday, January 8, 2016 at 11:56:50 AM UTC-8, ND wrote:

i know thats what moffat says to do.... but that's not a good maneuver if you are sharing the thermal.

Which is why I started with "someone who thinks they are alone in the thermal might" (if you look up thread little further).

It is perhaps another east/west divide thing that need to be considered in any solution. The thermals in the west can be very strong, as the sink can also be, and speeds are quite high by comparison. I'm not sure the same parameters are going to apply to both, as others have also suggested. That means, without further epiphanies, two stealth modes.