I've generally found Thai ladies to be excellent kissers. My ex girlfriend from Bangkok was particularly proficient, and enthusiastic...but only when she was drunk.
Mai mao...sniff kiss and a peck on the lips.
Mao nit noi, and the little tongue fella would begin to make an appearance.
Mao mak, and she wouldn't put it away!!
I used to wind her up quite a bit about it - she'd just blush and tell me to beat it. I think she'd only started practising a bit before I met her and was still a bit shy about it when she was sober....kinda cute though.
I'd say the longer the girls have been around farangs the better they kiss, and as Rider says, they're quick learners!
My guess is it's pretty uncommon among Thai only relationships though.
If he thought such indecency existed I'm sure we could rely on Khun Toxin to soon put an immediate stop to such immoral practices...
Never trust a hippy....