I'd guess that a lot of your issues on the day were stemming from it being really hot. I finished a half ironman last year in 100 degree heat with no shade but ended up in the med tent after the race due to dehydration. During the run I was having problems getting enough fluid into me much less food. Everything at the aid stations was out in the sun and therefore hot and hard to swallow. I froze my hydration pack bladder the night before which was a huge help. I also found during the run that ice provided at the aid stations was great in my jersey pockets to cool any food or gels. The cooler run off was nice on my legs too. I now swear by the margarita flavor shot blocks which have double the sodium of normal energy gels and won't do a race without some.
One other thing that I think I should mention is keeping the sun at bay on a hot race. I wore a white jersey and used arm coolers. If you're not familiar with them they're white sleeves that allow the heat out but give some good sun protection. Mine are from Nathan and I know Pearl Izumi makes some good ones too. I also modified my headsweats hat sahara style with some material from a football jersey to cover my ears and neck. It was great to dunk the hat in the ice bins at the aid stations and pour the cold water on the sleeves, I'm certain it allowed me to finish the race. The only other modification I'm thinking of is to make the neck piece into a pouch so I can put ice into it as well. That way the wind won't blow it around as much and I'll have icy water cooling my neck and back too.
Ok, the fashion police said I looked more like Lawrence of Arabia but under the circumstances I don't care. When you're highly stressed from the heat your body starts to shut down some systems like digestion so it's harder to get anything in. Do what you can to minimize the heat and it will be easier to eat and drink while you're on the course.
I hope that helps given it's been a while since the OP on this thread.
Andy
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