As I understand the "intact muscle" rule it allows an intact muscle to be cooked to rare using low temp. Provided it has not been punctured. Unpunctured, intact muscle need only have the outside 0.5 inch pass through 140 degrees within 4 hours. Something easily done at temps of 200 F or more.
Now if you inject it or insert a probe, you have changed the "intact nature" of the meat and should treat it as ground meat. This means the inside temp of the meat must pass through 140 within four hours. Usually requiring a temp of at least 275 F or better.
I’m just questioning the 5 ½ hour cook at 180⁰ to get the meat to 125⁰. It just seems long to me. But what do I know
