I just wanted to record the results of my test for other BPL users.
I was trying to simulate late summer arctic and subarctic conditions. I cooled 0.5 L of water to several degrees above freezing (maybe 3C?). The outdoor temperature was 25.5 C (78 F), but I couldn't do anything about that. I took a 4g rectangular Esbit tablet and set it up with the gram weenie Esbit stove right under the base of my MSR Titan 0.85L pot using the Ti-Tri as a windshield and pot support. These are just about optimal burning conditions for Esbit.
The 4g tablet burned out in 13 minutes, and the resulting water temperature was very pleasant — halfway between "warm" and "hot." It's a temperature I would gladly eat or drink.
If we are satisfied eating and drinking warm food/liquids rather than having to boil water, we get the following numbers: a single 14g Esbit tablet (they come in two sizes, as far as I know: 4g and 14g) can be broken into 4 parts and used over the course of a day to make a warm breakfast, lunch, and dinner, one of which (dinner) could consist of a larger volume of food requiring 2 3.5g chunks of fuel. In other words, one 14g tablet would heat 2L, or 2kg of food/drink to a pleasantly warm temperature. That's 140g of fuel for a 10-day trek or 280g for 20 days. The effective daily fuel weight would average to 70g and 140g, respectively. This is obviously very little. The reason this is interesting is that time would be saved by not having to gather fuel and build and tend fires. However, the capability to do so would still be there if necessary (Ti-tri cone).
In the past I have used pint-sized plastic jars to soak food (e.g. buckwheat) for a few hours (3-4 hours in summer temps or almost a whole day in cold temps) or more leading up to a meal. I'm pretty sure oatmeal, couscous, and dehydrated dinners require a lot less soaking time.
While the cooking time seems like a lot, if you start this first thing in the morning and first thing upon reaching your campsite, it wouldn't really take any time away from your daily schedule. You just do other tasks and come back to the food 13 minutes later.