When I did the GDMBR I used an aeropress.
Durable, light, fast, easy to clean, and makes a great cup of coffee.

http://www.aerobie.com/product/aeropress/

I rode NoBo summer of 2014.

We flew into El Paso and rode due north to Las Cruses then west along interstate 10 to meet the trail just before Separ, NM.

From this conjunction point south to Antelope Wells is a rode ride through the desert. Basically we traded one rode ride for another and I have no regrets about it. Getting to Antelope Wells without a car ride is tricky, especially considering how long you'll be forcing yourself to bike without a food resupply.

There's just not a big incentive to ride to Antelope Wells because all your gaining is a road ride.

http://www.carradice.co.uk/index.php?page_id=product&under=range&product_id=148


This rack is a great rear option. If your only planning on carrying a lighter single dry bag it would work great for the rack itself is light and can hold up to 22 pounds of gear.

Specifically for the GDMBR 4 days of food is the max I was forced to carry at a 60 mile per day average.

For water a large bladder is best. This method is very packable as the bladder changes size depending on water amount.

I rode the GDMBR in summer 2014.

From all the people all saw riding trailers they seemed to be less mobile than those with panniers/frame bags.

I would suggest for the dirt roads of the divide to use a frame bag, seat bag, handlebar bag combo. You want to stay light and compact to maximize handling.

Also by riding with a trailer you will double your possibility of flats and occur more maintenance issues. The goat heads of New Mexico would not be fun  on a trailer.

Stay light, stay compact, run tubeless, eat A LOT of food, and you'll have a great time.