Ch-ch-check out Obama's AH-Mazing final WHCD speech (above)!
But woe to the world, cause a nasty throat problem called Granuloma has prevented Mayer from singing live for almost two years!
During a benefit concert held in honor of those firefighters who fought the raging Pine Creek wildfire last summer in Montana — a benefit that Mayer organized himself — Katy Perry's latest lover treated the audience to a VERY special presentation…
Himself singing Speak For Me off of Born and Raised (above)!!!
And for having a nasty vocal chord problem, Johnny boy doesn't sound too bad!
SO glad to hear that seductive voice of yours, John…