Re: muay thai vs. jiu jitsu
I took Muay Thai some 8 years ago and i wrestled back in high school (not quite bjj but similar in being a ground game of sorts) The Thai style is a strong stand up game with strong striking techniques of the eight limbs (hands, feet, elbow, knees.) The bjj is extremely strong since most actual fights tend to fall on the ground so most bjj fighters are VERY comfortable lying on their backs knowing that they can still win the fight with their strategic locks and holds.
Can a striker stop a take down? sure if he is trained to know how to react when a grappler goes in for the shoot. Much like in wrestling if one wrestler goes in for the shoot, the wrestler who is in the receiving end has two angles to work with anything under 90 degrees and anything over 90 degrees. (90 degrees = having body in an upright position.) The shooter usually aims for the front leg of the opponent lets say for example the right leg happens to be in front. the fighter will shoot for the right leg for the take down. The receiving end fighter can either step back with his left leg and at the same time the right leg in which the grappler has shot for has to extend outwards away from the left leg to create a balance and thus causing his weight to shift forward (under 90 degrees) to cause the shooter to lay on their stomach while the opponent is laying his chest to the shooters back. Should the shooter be quick and shoots for your right leg for the take down it means you've gone over the 90 degree mark in which you are more likely to land on your back with whatever take down (single/double leg,)he chooses.
for the question can a bjj fighter protect themselves in a stand up game, sure. all styles of martial arts will usually have some defense in certain areas, but are more focused on the offense pending on the style being used. I remember watching a fight with Royce Gracie back in the early UFC fights and he was able to protect himself even in a stand up fight, but at the same time, his strong point was to take the fighter down. In order to do that it meant having to risk getting close enough to get hit in the face in order to plan his offensive attack which was to take the fight to the ground in which case then it was in his favor cause he was most comfortable on the ground and even on his back.
Either way you look at it there really is no wrong in either of the styles. If you prefer to fight standing up , Muay Thai. But if you are more for being able to hold your own on the ground then BJJ. You can't lose either way.