Without a gauge to show actual FE, I can only guess, but coasting in gear shortens the distance I can coast. When stopped, all I can go by is the tach: in gear is usually around 800 rpm vs 1000 rpm in neutral.
It also seems to depend on the speed sometimes; if I'm doing <45 and I coast in gear, the tach drops ~500 rpm but > 45 it doesn't drop noticeably (maybe 100?) and there's the engine drag.
Until I get the time to put a 'Guino together (I'm not paying for a SG), I'll just stick with my "neutral coast, stop in gear with engine on" policy.
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