LeBron isn't a choke artist by definition, however he has had quite a few runs of games where he played to a choke artist-esque level though. He really on has one, true to the definition moment, all be it an Epic, costing his team a chip, something-like a choke artist situation, and that was the Finals against the Mavs. It was in the choke realm because prior to that season, he did talk a lot of shit and set a lot of high expectations with that not 1, not 2... bullshit, so for him to thoroughly shit his pants the way he did does qualify as a 3rd to 4th degree Freeze up and Choke job...
Overall, he normally doesn't choke, but when he decides to Choke, he's one of the most committed to said choking players ever to choke. He makes sure there is no shadow of doubt as to his choking ability or execution...
Not a choke artists at all tough....