Please tell me if there is any difference between the 650X19 and 650X22 tires in an Ironman event. Thanks.
Comfort and Reliability (i.e. against flats). The 19’s I guess are a little more aero on your rim. I use Conti Comp 650’s ( 19’s upfront and 22’s in the back ) for racing. Great tyre. No issues yet. 
I don’t know if there are any specific tests to prove this but for me, I put a 19 on the front since I have little weight on the front. THen on the rear I have a 23 more for comfort and also feel like it is a little less likely to flat then a 19 on the rear. Purely ancedotal but that’s how I do it and have done it that way for ~15 years.
Thanks, I feel a little better about getting the new 22s. They just seem to be a stronger tire and more resistant to flats. I don’t think it will slow me down at all.
Slowman (dan E.) rides 22s (conti competitions, not the rims on his truck) if I’m not mistaken… I used to like mine. The 19s were just damn harsh