yep - see what you mean, but even with those 'diversions' I should be recording more mileage, not less surely? We do joke about how often it tells me I am off course and then back on course a few seconds late... really wondering if I should return it under warranty. It is only 6 months old.
Mine was the same, ended up a little misplaced for a while because of it, got use to it in the end.
No the reason the 200 shows more is because it didn't pause and recorded slightly more, I think there is some loss with the auto pause but because even though it stops you may well have stopped before it gets to the cut off speed, and likewise when starting, so they should even out, the 200, will have recorded for example a plot whilst stationary even if its only 10ft and enough of these will add up, I am not even sure how accurate a speed sensor is, its like all the sites bar strava gave me 40.3mph on Thur.