I wonder if he waited until he finished up his degree at Ucla to commit to a new school.
I guess if he's continued to work out at Ucla (chip Kelly was cool with supporting guys who decided to transfer out... his take was "Bruin for a day, Bruin for life"... but df is a different guy, and who knows how he rolls) and gotten into/stayed in good shape, it's not that hard as a rb to plug in. It's not like every other position on o, where "chemistry" has to be developed.
The rb has to learn the plays and terminology used to call the plays. TJ has now played for chip and EB, two extremely different nomenclatures. One terse, one verbose. And TJ picked out up as a true fr. So that capacity is there, I think.
Next is being able to read his blockers and pick the correct "path" (bang, bounce or bend). My sense is that great RBs are born being pretty good at that. We call it vision. We recognize it when a back just seems to magically run to daylight that was only visible if he was looking through his earhole. My sense is that TJ has always been really good at that. Unlike Keegan Jones. Who was never good at that. Watching TJ as a fr and SO, I rarely felt like he left yards on the table. As a JR? The run game was for shiit, and there were rarely any creases to run through.
The biggest flaw in TJ's game is his pass blocking. He's, frankly, rather poor at it imo. Especially compared to Zach Charbonnet. But that's probably unfair. Zach is the best pass blocking rb I can recall at Ucla.
If TJ wants to be a 3 down back at SMU, he's gonna have to improve that part of his game.