As the title says: which of the many circling approaches in the US National Airspace System holds the title of "circling approach that is flown most frequently?" My guess is it's the KTEB ILS 6, circle to RWY 1 procedure, but I don't know what other circling approaches in the NAS are frequently/commonly flown aside from the ones at KASE, which aren't really within the scope of this list, since the only reason they don't have straight-in minima is due to the excessive descent rate required for a straight-in approach.
As to why I'm asking this: it seems that the Part 142 training and ATPL checkride standards for circling approaches are causing a bunch of negative learning, as the training too often asks jet pilots to throw stabilized approach criteria in the dustbin. As a result, I was thinking it would be better to use a realistic form of circling (such as KTEB ILS 6 circling to RWY 1) when testing the ability of line ATPLs to fly circling approaches "in the box", as opposed to the downright unrealistic setups currently used (such as KMEM or KJFK, where the circling procedures are never actually used), as well as using night visual conditions for circling training and checking vs. trying to make people circle at minimums, which is dicey at best given current circling minimums.