Always an interesting question, but not the only approach to solving a problem. One can analyze a large number of events and characterize some aspects based on the goals, or one can more minutely analyze a single situation of interest and try to understand what the problems are and how to improve each one, testing carefully. Since each of us only has a few bikes, many arrows short of a statistically significant quiver, I'd think that Method 2 is the one to choose.

Re the Trek 610: Mine is a 1984 and has both BB flex and a low to middle BB drop (7.2 cm). When I was younger I tried to ride it pretty fast and pedaled through turns, and even with the skinny Shimano 600 pedals had pedal strikes a few times. One thing that always turns me off about tri bikes is the higher BB to ground clearance. You might want that. On the other hand, due to a typically forward weight distribution, tri bikes don't always handle as well in corners as a good road bike - a point in favor of the Trek 610. Ditto for ride quality, since mine is really pretty comfy.

In any event, I'd suggest getting the best fitter in your area to recheck your fit and see if there are any optimizations you should make. Your 610 will be at her best, and THEN you can see if she's up to the task. If you change the position, do it early enough that you have time to acclimate before the event.