Exactly why a remote reservoir works much better in the "long run". The internals of the remote reservoir itself are less than half filled with fluid. The tail end of the reservoir being empty(nitrogen) is turned into a true heat sink as the reservoir is aluminum. If we can all agree that the fluid "does" exchange from the res to the body, it's a no brainer that the reservoir does work like a small radiator...
Yes, as I alluded to in my last post, if you want to understand the system you must take into account the shock's ability to release heat to the atmosphere (conduction, convection, radiation). Heim joints (with just a little teflon maybe) could actually conduct heat away from the shock if the shock gets hotter than the mount and frame. Poly mounts are pretty good insulators. Surface area impacts how much heat is radiated and transferred to the air. So now (if we are still talking 2. 0 Fox RR vs. SAW 2. 25) you must take into account the larger diameter and longer main body length of the SAW (taller mounts means a longer shock - usually). Not that I am arguing anything specific, just pointing out that merely saying RR means more surface area is not true - need numbers. If I were to
guess, I would put money on an aluminum body shock dumping more heat due to it's thermal conductivity - but then there's those mounts . . . I hate guessing. But, in this case, I don't think the shocks capability as heat exchangers is the real story . . .
In desert racing, where shocks are working continuously turning suspension energy into heat and dumping that heat to the environment, the shocks could actually reach
STEADY STATE. That means, if they were designed well, they reach a temperature where they are dumping as much heat as they create. In order to reach this state at a temperature where the shock can still function, the shocks capability to dump heat is very important. This is not the application we are talking about here.
Neither of the systems I think we are still talking about were designed to perform that long at that rate of heat exchange - that's what the 2. 5s and up are for. The shocks heat up
because they are generating much more heat than they are releasing. These systems perform for a period of time, and then fade. In that application, heat capacity has a greater impact on determining how long the system will work before fading.
Now if both manufacturers are claiming the last paragraph is not true in so much as these systems can perform all day, then I am not sure the temperature they run at means a darn thing. Not fading is not fading, and higher temps may mean a system that is tuned to get more work out of what it's got - or not.
And just to defend physics - anything that is empty is by definition a horrible heat sink. Thermal mass makes a heat sink. Empty is also an inefficient radiator - the oil needs to be in contact to transfer heat to the body (luckily, aluminum is a good conductor). That's like saying running your cooling system a little low so the radiator is half empty is a great way to keep your engine temp down.