Does Av-Blend work?

Yeah, this is a conundrum... It has a bluish tint to it, which I assume
that word is due to the active chemical molecule/element, as the
usual liquid, lubricant stuff is normally clear...

Now, the local FBO rented C-150's for decades, and for decades had
stuck exhaust valves on a regular basis (renters running full rich)...
One time they had two valves stuck in one week and lost money on
cancelled flights and the owner, despite being tighter than the bark on
a tree, sprang for a case of AVBLEND... They never had a stuck valve
after that...
Yup, anecdotal...
Yes, not valid statistically...
Sure does seem unlikely...
Goes against my suspicious nature...

Now fast forward to 2004 and this airplane owner had his first stuck
valve in four decades of ownership, and multiple airplanes... So,
guess what I am now slopping into my engines?

cheers ... denny