Muay Thai is serious business. Those guys don't mess around. They punish their opponents. If you can't fight, you better run from a Thai boxer.
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Strength is important in grappling and wrestling but it is not near as effective if the person does not have their balance. Also overly relying on it can fatigue your muscles quicker and burn them out and render your greater strength useless. So a better fighter will also rely on leverage when and where they can and there are some techniques that require balance, leverage, and speed rather than power to use effectively. While a fit, strong, athletic type person might be able to win over someone like what you mention they are at a big disadvantage in so many other ways and the experience factor in all this is a huge factor even if we are just talking about an amateur.
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Strength is one of the most important factors in a fight, others are: speed, experience, technique, conditioning.
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my brain

2- does the "normal" guy have a weapon?

3- is the mt guy in anyway physically impaired, drunk, asleep or has his back turned?

if the answer to all of these is "no" then probably not.

then again- it is an "amateur" MT fighter, you didn't say that he was any good he could be 0-5 for all we know and just keep entering amateur bouts because his school does.

odds are I would say no.
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If you're fit, you stand a chance fighting someone, but remember, he has gotten comfortable punching and kicking. The more he does that movement the more confident he is doing it against you.

If you're untrained and get in a fight with someone who might be, and you are fearful of losing your life or ability, don't try to play his game. Attack them hard fast and unrelenting. Be confident in your movements and know and want to hurt them. You won't shame them so don't try, you won't look good so just go, and you will get hurt so accept it.
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Bottom line the way to get the best out of a fight is not to get in one.
read "How to Win Freinds and Influance People"
Dale Carnegie

hell i am uncoordinated! i have no natural talen!, and have asthma and im winning tons of sparring tournaments! its because i work as hard as i can! its not about being normal, its about working hard and using what you have
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Strength only matters if the individual wielding it, knows how to do so.
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In the ring?

Not a chance.
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drink in moderation
it breaks down to this:- smaller rounds of exercise throughout the day……I walk in the mornings, practice boxing twice a day, go to the gym in the evenings.

have a strict timetable for eating,try not to eat after 7-7.30,avoid sweet and sauces/gravy of most kinds.Have three basic meals and try keeping the food as simple and less complicated as possible.

Do breathing exercises.yoga will strengthen you up like you will not believe.It also cures back pains and muscle pains in the elementary stages itself……………in the advanced stages it works pure magic

to give you an example here try one of the exercises by the one of the greatest catch wrestlers in history http://www.sandowplus.co.uk/Competition/Burns/lessons/lesson01.htm the breathing exercises look simple but they should both exhaust you and make you strong if done properly.
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