Valid way to check valves?

[FlipCoupe]

So back when i had my motor apart I had my friends dads race mechanic check my valves. (His dad races in a thumper class dirt racing or something) Anyways the guy took the head and flipped it upside down, he then filled the valve area with gas on all 4 cylinders and let it sit there. Nothing leaked through so he dried up the gas with a shop towel and said the valves were fine.

Input?

btw, im going to have the head cleaned and resurfaced when i rebuild my KA in about a month, Im just wondering aboutt his guys method.

[breadbox]

whenever you get the head cleaned up, they will tell you if anything is wrong, and just because the valve seats doesnt mean its a good head. when you get it back it should be new looking, definitely get new oil seals.

I guess its a valid way to see if they seat properly if you had the head out.