Finally got back to this. Here's what I found. In order to get a true rolling boil using the esbit+jetboil combo I measured the distance between the Trail Designs gram cracker for use with a hardcounrty 3 cup pot. It just so happens that to reproduce that distance on the Jetboil, all I had to do was allow the heat exchanger to sit below the cone, and the neoprene sleeve to sit above the cone.
In order to set this height, I used 3 zip ties to create a lip on the jetboil cup.
Using this config, at 47 deg light wind, 2.5 cups + 1 ice cube, it took 6 minutes to achieve steaming water ( plenty hot for tea and instant oatmeal if water is pre-filtered ); it took 10 minutes to acheive a rolling boil. The rolling boil lasted for an additional 6 minutes. This gives a total burn time of 1 cube at 16 minutes.
Once the rolling boil was achieved, I was curious if the heat exchanger actually made a difference in boil time. To test this, I did a boil test using the gram cracker with a cone and an evernew ECA418 pot frying pan combo. The time to boil was exactly the same as the jetboil combo. 6 minutes to steaming water, 10 minutes to rolling boil, 16 total burn time. This appears to mean that the heat exchanger is not helpful to decrease boil time or fuel efficiency.
The next set of tests were setup to determine boil time fuel efficiency of the folding titanium esbit compared to the gram-cracker cone jetboil combo. When setup with the Jetboil, steaming water was achieved at 6.5 minutes. Rolling boil occurred at 11.5 minutes, but was not sustained more than 1 minute longer. The total burn time was reduced to 12.5 minutes, where the last minute of burn was not hot enough to maintain the boil. Additionally in this config, the cook pot sat much lower then the cone+gram-cracker combo. This meant the neoprene sleeve was down inside the cook environment inside the cone. This resulted in a very hot neoprene sleeve which essentially rendered the sleeve useless for protecting hands from the hot cook pot.
I did find that the folding esbit stove worked very well for frying eggs, and for making tea in a GSI Ketalist. But the fuel def didn't last as long and the rolling boil only lasted 2 minutes.
Finally, I did a test using alcohol to be sure that it made sense to continue with the esbits. I tested this by setting up a jetboil+cone+traildesigns 12-10 stove (with priming ring removed)+ 2.5 cups+1 ice cube config. As others have documented, it takes all of 3/4 oz of fuel to achieve a rolling boil in 8 minutes. Then it took an additional 1/4 oz of fuel to keep the rolling boil going for an additional 3 minutes. So that is 1 oz fuel alcohol vs. 0.5 oz fuel esbit.
Here's a picture of the finished product. The zip ties have been trimmed and then tucked under the neoprene sleeve. This helps keep the zip ties from getting caught on anything in the pack. It also helps keep the neoprene sleeve from sliding off the jetboil cook pot. I also trimmed the black hand loop from the neoprene sleeve. But I left the little square thumb pad which makes it much easier to hold the cook pot. I also added a thermos top ( cup ) to the setup after repeated burns while trying to sip straight from the jetboil cook pot. I avoid using the plastic cup that attaches tot he bottom of the jetboil because it could get contaminated by the esbit residue on the bottom of the cook pot. I also found it was ery easy to store and re-light partially used esbit fuel cubes. When making hot water from filtered water a rolling boil was not required, and I was able to recover almost 50% of the cube. As such, I've added a small plastic pill container to store the partially used esbits. Total weight of Jetboil+cone+gram-cracker+fire steel+lighter fluid+stormproof matches in metal case+spoon+cup+container for partially used fuel=13.8 oz
note: I have left a partially used fuel cube n the container in the picture, but the fuel was not included in the weight.
1) The traildesigns gram-cracker solid fuel stove provides the most efficient fuel usage compared to the esbit titanium folding stove and compared to no pot stand windscreen at all
2) The heat exchanger on the bottom of the jetboil cup did not decrease boil times or increase fuel efficency when used with the traildesigns cone and gram-cracker. Therefore lighter cookpots (example MSR Titan + vargo titanium pot lifter) would render approx 5 oz of weight saving.
3) It's possible to setup almost any cook pot for use with the traildesigns cone+gram-cracker using zip ties to set the appropriate distance between gram cracker and stove.
4) The benefits of using the jetboil cookpot vs. a traditional cookpot are diminished because it is somewhat difficult to to drink directly from the cookpot. This requires the addition of a drinking cup at additional weight penalty. However, the jetboil is unique in that the residue left over from the solid fuel cube is not as messy because the residue is above heat exchanger and thus doesn't touch any other gear.
The biggest benefit of the jetboil vs. a traditional cook pot are the packed size of the cook kit. A traditional cookpot may not be able to easily stow the fullsize cone windscreen/potstand. Sidewinders that completely stow in the cook pot are certainly available for the MSR titan 1L and 1.5L. Not sure how bulky these are compared to the jetboil setup. I'd like to get one and compare how well it will pack up in my 30L solo-overnight pack. A Jetboil-Ti would also close the gap to approx. 3.5 oz between the Jetboil config and a traildesigns sidewinder. I'm also looking at the vargo bottle pot ( http://www.vargooutdoors.com/pots-mugs/titanium-bot-bottle-pot.html#.UUybmRJHerA ). These weigh about 2 oz more than the MSR titan 1L and may be a compromise solution between the Jetboil Cookpot and a traditional cook pot.
Hope his helps,