Had an interesting dilemma recently, when the dean of the college I teach at (part-time) invited me to oversee a three-week film project in Beijing, working with students at a university there as part of an annual exchange program. It would be in July; I'm tackling IMMT as my first full distance event in Aug. - clearly it would destroy my race experience based on the planning to get to this point.
Much as I'd've liked to get my foot further in the door at my place of employment - not to mention pull in a good chunk of pay, being a "freelancer" - I told her thanks but no thanks/not this time/keep me in mind for next year (she then mentioned giving a master class there in October during an animation festival... much more palatable to me & it sounded like I'm still in her good books) Speaking of palatable: before you go thinking this is some exotic experience peppered with glamorous day trips, previous participants said it is not much more than relentless 12-14 hour work days, cafeteria food, and short sleeps.
This would fall right at the height of my schedule's peak, just before the taper begins. I felt sufficiently committed to the IM that declining the offer wasn't all that hard, so I'm not asking your opinions of "did I just shoot myself in the foot?" (though it might be funny to hear your perspectives) but it did make me wonder if you've experienced any [b]external[/b] "tests" of your training resolve in your IM journeys.
Edit: BTW, It came after I relented to attend a family function across the country in late-July by juggling my week; will now call one of my travel days a rest day(!) and the entire flight/visit/return has been trimmed to about 40 hours! Perhaps I was punch-drunk from this compromise, and felt I had to draw a line in the sand.
This is starting to remind me of the trials and struggles detailed in Joseph Campbell's writings (the Hero's Journey)