I notice the CLEAR checkpoint at MCO when heading over to the TSA PreCheck lines, and I have never seen more than an occasional business traveler use it. The PreCheck lines move very quickly, even when the regular Security lines are very backed up. During the 6+ years that I have had PreCheck, I've never waited more than a couple of minutes to reach the I.D. checkpoint at MCO and usually no more than about another 5-6 minutes to complete the screening process. For those who travel frequently, including international travel, Global Entry, which includes TSA PreCheck, is a better option.
A couple of years ago, I was standing in one of the PreCheck lines at MCO and recognized the person in front of me; he was a well-known travel journalist whose contributions include authoring travel books, producing and hosting his own weekly radio broadcast, and serving as the travel editor and a contributor to a major TV network's morning show. He was using TSA PreCheck - not CLEAR. By the way, he was very friendly, and we had a nice chat while working our way up to the metal detector. So, you never know who you might meet in the PreCheck line!
Here is a good comparison between CLEAR and PreCheck:
Is PreCheck or CLEAR better?