A few weeks ago, I was a guest on the weekly Going In Circles podcast, which is hosted by Chuck Simon, the former trainer who's also a top-notch writer at his blog, and Barry "The Sniper" Spears, an excellent handicapper and well-known figure on Twitter. Simon asked for my opinion on which stallion I'd consider to be the most influential of the past 50 years. You can listen to a nine-minute clip of the conversation here. My answer? Claiborne's iconic Mr. Prospector, of course. The clip generated quite a bit...