For anyone interested, we’ve done some extensive research about this since Blizzard’s response which can be found here:
https://github.com/magey/classic-warrior/wiki/Crit-aura-suppression
I’ll quote the TLDR:
Weighted average by number of attacks for all suppression results (without including the 1% aura crit tests which seem to be suppressed entirely) gives ~%4.84 average suppression with a 95% confidence interval of ±0.17%, meaning the suppression to aura crit is likely ~1.8%.