One of the many things I'm sure I've stressed during the time I've written this blog is that for mixed martial artists, the training never stops. No matter how long they've been competing, no matter how many fights they've had, no matter how many hours upon hours upon hours they spend in the gym, they're always looking to improve in all the different disciplines that make up MMA.
If they wanted to learn more about Muay Thai, they might watch something or take part in something similar to this, courtesy of Columbia Maryland Mixed Martial Arts, where they learn the finer points of striking and find out what sets a style of striking like Muay Thai apart from traditional boxing.
Submission defense is also key, so a video like this would come in handy, courtesy of Garfield BJJ in Arnold. A fighter can put their opponent in a submission at any time, especially if they're well-versed in the ground game as all of the great submission specialists tend to be.
Combining styles like Muay Thai and submission grappling would make any MMA fighter truly dangerous. But no matter what style a fighter specializes in, the key is to be the best in all areas if they want to be the best overall. The ability to avoid resting on one's laurels is what separates the contenders from the pretenders.