I'm sorry, but I don't get it.
What's the rush? Who needs a large tattoo that quickly anyway?
Is regular (shorter) sessions too much trouble? Even if you are traveling, I see no need to do 3 full consecutive days.
I'm gonna stick my neck out here and say that every sleeve that I've seen (in person) completed in marathon sessions or super-close consecutive sessions heals pretty rough. I'd love someone to prove me wrong and i hope someone can but I don't see how you can heal a full arm while maintaining some sort of normal life (which includes moving your limbs, going to the toilet, moving food to your face etc.) without having some colour drop-out or whatever. I find healing larger tattoos to be miserable at the best of times, particularly around the ditch, elbow, armpit etc. For me, marathon consecutive sessions means another trip for touch ups, which negates the need to finish in a short space of time anyway.
It usually takes just a little more thought from the tattooer to finish smaller sections of the tattoo with a mind to extending it later if the client doesn't want to live with an un-finished looking tattoo, or the manner CaptCanada described at the end of his post above. This can still be tough to heal, but is a more efficient use of time, particularly for people who travel long distances. But I guess you don't get so many bragging rights, just a solid, awesome tattoo.
Please bear in mind that I have occasionally and begrudgingly, tattooed the same person on 2 consecutive days to finish a large tattoo before they leave the country/go to prison or whatever, so that probably discounts my opinion.