Heres what he did wrong:

1. The steaks are too thinly sliced, they should be at least 1" but 1.5 – 2.0 is better.

2. He said to use rough cracked pepper, dont. Use fine ground. The rough cracked stuff will lift your steak off the pan preventing a good sear and possibly burning the pepper.
(If you are cooking over a charcoal grill, the rough cracked pepper is better. It gives little spikes of pepper flavor that I really like, but dont use that in a pan)

3. A steak should be served rare or medium rare. His pan wasn't hot enough to get a good golden brown sear and be cooked med-rare. The pan needs to be ripping hot, if your smoke detector isnt going off, its not hot enough. That steak came out med or med-well. If you have a charcoal grill, that is the best. For the home cook who must do it indoors, learn the reverse sear method and apologize to your neighbors for your smoke alarm going off all the time.

4. Save the touch temperature reading for the people pumping out 70 steaks a night. Youre doing a few, you can take the time to measure the temperature and be sure its safe. Besides it takes a while to accurately gage it. It takes practice like any skill. If you want to practice it, simply touch it before resting and learn to get a feel for whats right. But use the thermometer to be sure its right, first.

5. Resting. He pulled them, slapped them on a cutting board and said let them rest. In fact you want to put them on a sheet pan with a grate (best to use the same one you used for the reverse sear) and cover them with tin foil. Let it go 5 minutes unless it's big like a 3+ lb tomahawk, then give it 10 minutes.
After cutting and plating, pour those juices collected in the sheet tray back over the steak.

As to why Im watching if I dont think hes good (his cheeseburger video is trash too), i dont personally like butter basting as he demonstratedin the video. I love butter but on potatoes or vegetables (and my cod). I feel the butter competes with the beef flavor and I just love the beef flavor, it doesnt need butter. But I developed a recipe tonight that I think will give me much of the same benefits of the butter basting, without the beef being overwhelmed. I just needed to confirm the herb used was thyme and not rosemary.