Dots and dashes and plusses and minusses are a pain without doing some
secondary processing on the flight track. In the scales where the trackdots
are laid over one another you can't discern where there was lift and where
there wasn't because the plusses and minuses all bleed together.

I'm leaning towards the following solution, track is laid down in a single
colour and where a 'significant patch' of lift is detected simply pasting a
lift symbol over the trace, the same for sink areas. In the smaller scales
making a selection of plus and minus signs or alternative colours.

Ian