Overeem... both of them As a Thai student myself the chap kho (clinch) is a big part of what we learn as a khao trong (straight Knee) to the rib cage will break a rib if used correctly. A take down from a clinch is very dangerous as if you eat a knee when dropping levels you will be out... a leg sweep is a better option as you will have less chance of being elbowed. Lynchburg
A good clinch can work though. If you are keeping your hips and feet back and timing your strikes while manipulating the guys physicality with your neck tie then it can work well. Just easier said than done. More guys will probably know how to shoot a double leg, no matter how sloppy rather than control someone at the same level Rua and Silva would.
Thats when it works... Franklin is basically the same fighter as Anderson but on a much lower level. Look at the fights...he wouldn't try it against Hendo or Chael.
Silva uses em from time to time but not so much anymore cuz he has a kick to the face that will KTFO you out ask Vitor
witch brings us full circle back to the question of "why the no repeated knees like in the pride days" answer being: "in the pride days the fight game was evolving where the unaware when dealing with the MT clinch simply didnt RESPECT it nor have experience DEALING with it, thus the REPEATED knees until the unaware just crumbled" now a days seasoned fighters if caught in a MT clinch have their MENTAL ALARMs from their TRAINING go OFF asap. Thus it turns into a CAT and MOUSE game when trying to secure the MT clinch, thus the trend of more SINGLE knees only thrown when the close to perfect positioning is SET with a MT clinch, witch will nowadays only last for a split second or two.
it seems like its hard to do a good thai clinch without being taken down..espically if you arent a real expert..and have only been training it for a few years (which is true of most mma fighters) maybe a guy who started both muay thai and wrestling at a young age....or at least has been doing thai for years and years and also has a strong wrestling base (like rich franklin) but for most mma fighters it will be hard to keep up.
Committing to it is the key. You've really got to get in close with the elbow strikes and pull down hard on that neck with your forearms tight against the head. Throw those skip knees as hard as you can then throw the guy and blast him with a kick to the gut. Simple. :blood