It sounds like horse*hit. Even if you can break your body's metabolism so you pass food without extracting nutrition from it, this is a *huge* waste of money and resources if the requirement is 2500Cal - you could feed two people (or one person and a *huge* colony of tapeworms) with a food budget of 5000Cal.
*Maybe* if you are doing 12hours of *hard* exercise per day you might close in on that kind of Calorie requirement, but most people, even those who are active don't work massively hard or for as long as that, but digesting that much food? Doesn't sound like fun.