I don't know any other definition of "myth" other than something that doesn't exist.
Reversals exist.
"Outlier" means a data point well outside the norm. Reversal success rates are affected by a *lot* of factors. However, up to 95% success in restoring motility has been recorded (from the Wiki article).
There are certainly points at which a success *would* be an outlier. Speaking of the procedure in general, it is more of a coin toss or bell curve.
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