I have a Karate background and prior to that I had a background in
Taekwondo.  During my years in Karate I trained with a number of people
from different arts and my focus was always on what worked best.  I spent
a lot of time getting the ball of the foot front snap kick and round house
down.  I also have a nice technical side blade kick and back kick and I
managed to keep and improve my crescent and hook kicks from Taekwondo. 

I am the first to admit that Thai boxing does a lot right.  But as more
and more gyms pop up that are MMA from the beginning I am seeing people with an
exclusive Thai background.  In Karate I was always open to picking up
something new but I have seen a weird attitude that a lot of the Thai guys
think that they have all the answers.  A lot of these guys don’t know the
history of Karate/Thai/Savate kicks merging to form the Dutch style.  A
lot of these guys have never read the Tao of Jeet Kune Do and seem totally
oblivious to understanding why a strike is affective or not and just repeat
what their instructors tell them.  I thought that the early days of karate
helped pave the way but it seems like the MMA guys are making some of the same
mistakes that a lot of the original schools made.

Here is what I am getting at: The Thai boxers are not taught to use the ball
of their foot.  The tee kick seems almost useless compared to the classic
front kick.  The round kick does not use compression of the leg but rather
drags the fully extended leg through the air.  Throwing your lead arm out
to create torque exposes the face and is totally unnecessary if you have good
balance.  The thai boxers leans backwards very much like the taekwondo
stylist but instead aims low.  They use the rotation of the axis over the
hip to whip their leg and create power.  It works but it has a much lower
margin of error then leaning over or on top of your kicks where you are using
your body weight behind the kick. 
Finally very often they do not “re-chamber” but rather drop their kicks
where they land.

I have seen guys spend hours doing the same shin kick over and over
again.  Instead of learning balance they
expose their face to a counter.  Instead
of leaning over or on top of their kicks they lean away meaning that they are
more susceptible to having their kicks jammed. 
If you look at Muay Boran it looks almost identical to Karate or
southern Kung Fu.  The leaning back was
developed to protect fighters in the ring not give them the most effective
kicks for combat.

Just my two cents would like to hear your thoughts.