I love riding my fixed gear (and have only ridden it in SS mode a few times). I don't think it trains me, especially at my age and with my years in the saddle, to be a better rider on my geared bike (getting out of the saddle, riding seated, spinning, climbing, texting while spinning, drinking lattes at Starbucks, etc).
Definitely it:
1) Makes me feel like I'm 25 again, since I see so many younger people on fixies and single-speed bikes and
2) Gives me better workout on the fixed gear bike, because there's no coasting (which is one reason I like riding fixed rather than in ss mode).
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