the last time i was worried about the re percentage, i started keeping track in a spreadsheet.
691 greens re'ed- 132 successful = 19.1% (tooltip says 20% chance)
316 blues re'ed - 35 successful = 11% (tooltip says 10% chance)
statistically, this is a pretty small sample size, but it was good enough for me. I've gone 45 attempts without a successful re. I've also done 3 in a row successfully.
Toolip is correct.