Since this question didn't get traction in the High Elf Megathread, I might as well ask it here instead.
It was so effective in the Bazaar like the pro-Alliance Blood Elves suddenly wants Alliance blood; this could basically lead all of the Thalassians back to their fold. The Kirin Tor pretty much didn't care that their own people were massacred in Ambermill and that Sylvanas mind controlled Koltira, so I doubt they'd even care about this if the Blood Elves did it.
Quel'lithien Rangers still hating Lor'themar? Zap!
Need a forward base in the Hinterlands? Zap!
That priest is still an Uther fanboy? Zap!
Some stubborn wife in Loch Modan chooses Alliance simps instead of her husband? Zap!
Want to secure a place in Dalaran and need to assure total approval from the neutral humans? Zap!
Purge of Dalaran? Zap!
Sylvanas wants her lil' sister back? Zap!
Basically they could just sneak some of their Priest Police towards the High Elf enclaves and unleash their mind wipes. Maybe this way the High Elves would have been erased out of existence completely or 99% at least.