I rode to AK in 06 on an 04 DL650 with a buddy on an Aprillia Caponard. We actually trailered the 42hrs from Atlanta, GA to Kalispell, MT to split that long boring drive, save time, and save tires as that was a concern too. Our trip ended up being 6500 miles on the bikes, but would have been over 11k had we ridden the entire way. I got a flat tire 60 miles out of Deadhorse on the way back down the Dalton. We both had air pumps and plugs and stuff to fix the tire, but the type of puncture and the rough roads were playing havoc trying to keep the air in the tire. We did what we could to plug the hole, but it was still leaking down. I ended up pumping it up to 50-60psi and riding as far as I could before it would go flat again. Rinse and repeat many times over. After a few times in a row of using the air pumps, and then putting them away hot, another problem came up. Those little air pumps have plastic gears that get hot and we could tell they were giving up. Long story short, we lost both of them before I made it back to Cold Foot the haly way point. My last air fill up before Cold Foot was waving down a car and them having a pump to use. Finally once in Cold Foot, found a truck driver with a massive plug kit that finally sealed my tire good. Of course the tire was shot by the time I got back to Fairbanks from riding on it flat so much and had to replace it to go home.
I don't remember exactly what the new tire (Tourance) cost me, but it was outrageous and I'm thinking well over $300 in the end. My buddy got a flat later on in the trip, but we used slime on his which worked much better he still made the whole trip on his Tourance, but at 6500 miles it was gone. The rough roads up there really wear tires a lot faster then what you are used to.
So, my point is, if I was doing the trip again today, I would definitely do the dark side to do the trip on one tire. There's plenty of people on this site that have proven it works and works well. I'm about to try it myself on my next tire change and looking forward to it on my trip to Nova Scotia this year. Yeah, you are going to probably get more flack about this than you can shake a stick at and yes you can obviously change tires up there, but you never know what else you'll run into. The choice though is yours in the end and no one elses.
I would read up on this thread and make your own opinion from whats been discussed - Darkside 1st ride
I think if you did go this route, I would use a snow type tire like Randyo is using so you have better traction in the mud/dirt.