What I found happens if you take a stronglift program somewhat seriously being fat is that you typically maintain or slightly decrease your weight but you can lift like 250lb so that means you at least made some kind of fat muscle trade off but its highly satisfying anyway, and you cardio/ability to run increases greatly, but the problem is that you will have various stabilizer muscles and stuff that is not used for running so you may suddenly as a previously heavy man be able to run a seemingly long distance if you have been doing heavy lifting for a while but expect all the auxiliary stuff to hurt/encounter serious damage.
I kind of think (though I am very uneducated here) that the type of muscles Dave Jones talks about is more grown to have high blood flow and possibly production of glycogen or whatever, while muscle grown for heavy/sporatic activity will not have as much infrastructure in it dedicated towards getting large volumes of blood into it or using blood to produce energy (I have to recover for a long time).
Probably for most labor you will find that the endurance type muscle is more useful, however, I do wonder what the effect on heart strain is, I would expect the endurance type muscle to have higher fluid resistance because of its possibly higher surface area, so if you have a huge amount of it, it may be slightly more stressful on the heart then the other type, but I am pretty sure it would still be far better then fat.
I got this idea by kind of following the BB community and noticing that many people (well steroid users that basically do heavy weights endurance (freakish)) seem to have an abnormal amount of heart problems.. and the debate is if it is purely due to steroids, related to 'good looking' obesity (mass term only, not fat, meaning that the mortality is the same as for a regular fat person), or a type of muscle growth that has a very high surface area so it acts as a strong resistance for the heart, possibly making the excess of such tissue more dangerous then an excess of fat for the heart. (but I suspect the people are still much much happier psychologically)
Based on others peoples comments (taken with a grain of salt), it seems that the mortality of heavy muscular is higher then equally heavy fat(tissue) obese people, so there might be something here, but this would require me to put alot of effort to research problems I don't have or really care about too much . This would be people that weigh like 300lb.
May be of interest to study if you want to make the choice between TRENT, methamphetamine and do heavy squats till exhaustion/death every day , or crushing 6 bags of family sized doritos every day