I think there is a lot more to the term "choker" than simple won-loss record. But that is only my hack opinion. Other things that could be factored in are:
--Opponents avg. against in televised matches (at the risk of sounding Loschetter-ish)
--Sudden loss of look. (Who among us, pros and amateurs alike, hasn't gone 250-something, 160-something, 240 something?)
--"Different" ball reaction when the shots get more critical. If/when he whips a ringing ten when needing a strike, that is tons different than leaving 4-thru-the-face, or double nuts under the same pressure.
Again, that is just my hack $0.02.
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If I ever saw an amputee being hanged, I'd just yell out letters. --DM