I guess I should have suspected that it had been done before. Thanks for the link. Good benchmark there. Incidentally, if you change the qshuf sub to be 
sub qshuf {
    sort { .5 <=> rand(1) }
    sort { .5 <=> rand(1) }
    sort { .5 <=> rand(1) }
    sort { .5 <=> rand(1) } @_;
}

[download]
The Std Dev drops to competitive levels, but the performance drops to last. Two or three calls to sort isn't sufficient. It was surprising to me that the time required for two chained sorts is so much more than for one.
Caution: Contents may have been coded under pressure.

In reply to Re^2: Is this a fair shuffle? by Roy Johnson
in thread Is this a fair shuffle? by Roy Johnson

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