I like nerdbot5000's explanation of how he skids:
Originally Posted by nerdbot5000
1. Pedal a bit, and then ever now and then go limp and let the pedals push your legs around
2. Do the same thing, but this time, as the pedal come backwards and up, let it push your body off the saddle. Just relax and stiffen your back leg a bit to do this.
3. Do the same thing but try to completely straighten your back leg as the pedal comes backwards and up, and let it push your body off the saddle
4. Do the same thing as #3, but when the pedals start to approach the point where the cranks are parallel to the ground, resist with your front foot by pulling. You should definitely feel a point where there is a great resistance to pedaling, and that should be when the cranks and parallel with the ground.
If nerdbot5000 doesn't teach for a living, he might consider it.
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A while back during a prolonged medical treatment I geared
WAY down just because I didn't otherwise have the strength or energy to ride.
Sixty gear inches.
Anyway, I really learned to spin, and I found myself inadvertently skidding while back pedalling.
It would happen when I pulled up with the front foot.
If 60 gear inches seems low, on my severe weather Ice Bike I ride with 50 gear inches; and, yes, the world goes by rather slowly.
At 50 gear inches I have to consciously avoid skidding because skidding tears the studs out of my tires.