A couple of considerations
- Jason Horn, 45-49 AG, 70.3 Sunshine Coast- 19:10! Top Pro was Clayton Fettell at 22:08, so not a short course, just SUPER fast!
- Mike Shafer- AG- IM Canada, 1994, Penticton- 42:xx (42:30 ish). All time IM swim record until about 2008ish, broken at a somewhat short IM Austria, and of course later at down current swims in NY and Chattanooga. Still probably the fastest legit IM swim ever, and only a couple of weeks after getting out of a wheel chair from a horrific bike accident!

Regarding the 19:10 vs 22:08, i think the 19:10 must have been current-assisted, i.e. the current shifted between the pro's swim and the 45-49 wave. I say this b/c the 1500 m WR in the 50 m pool is 14:31. Given that Sun Yang had the benefit of starting off the blocks plus 29 turns, that adds up to at least 20 sec more in OW, so we can hypothesize the 1500 m OW WR at around 14:51ish, or about 59.7 per 100 m The half iron swim is 1.2 miles or about 1930 m. At best Yang could maybe hold 1:00.0 for the 1932 m swim but that still implies a time of 19:18. Therefore, the 19:10 can not a true non-assisted half iron swim time since it is just not believable that some 45 yr old age grouper is going to swim faster than WR pace. Sorry. :)

I CONSIDERED YOUR THEORY OF “CURRENT” BUT FOUND THATI UNLIKELY AS IT WAS A ROLLING START, AND HIS TIME DIFFERENCE TO THE NEXT BEST IN HIS AG WAS 5 + MINUTES, AND HE WAS 4+ MINUTES FASTER THAN ANY OTHER AGE GROUPER. I AGREE IT IS CRAZY FAST, BUT CANNOT SEE ANYTHING SUSPECT, UNLESS HE SOMEHOW CUT THE COURSE, BUT HE WAS NOT DQ’D. PERHAPS SOME OF THE AUSSIE SLOWTWITCHERS CAN COMMENT?

The 42:30 is somewhat more believable but still a bit doubtful. Based on the fastest OW times for the 5K OW swims, i'd guess the 2.4 swim WR, if it existed, would be around 41 min. While it is at least possible that an AG tri guy could swim that fast, i still kind of doubt it. AFAIK, Lars Jorgenson is the fastest 1500 m swimmer (15:09 lcm at the '88 Oly Trials) to ever do triathlons and he only went 46-low at Kona back in the 90s. Based on the recent discovery that the Kona swim course was about 200 m long for many yrs, and hence they shortened it in 2016, then Lars's time might be 43:45-ish on an accurate 3860 m course. Of course, he was probably a bit slower in the water due to all the time spent on the B and R, and hence less time and energy for swimming, so I'd guess he might have *only* have been able to 15:45 for 1500 lcm at the time he set the Kona record.