Alcohol Stove vs Jetboil Sol Ti - weight savings, is it worth it? Yes.
Getting back on track, it sort of depends on the hiker. If you are in a group, simply require every person to bring their own stove, pot and windscreen. For 5oz, this is an easy carry. For 2 people, it is possible to split the weight of a Jetboil among both or even three people. For larger groups, every 2-3 people will need another stove up to the maximum trail sized group.
I think the weight issue has been pretty much resolved, because the discusion has moved to other things that need to be factored in. Light weight packing is not ALL about weight, something we often fail to consider.
Anyway, alcohol is usually the lightest up to ten days. For longer times out, you may need to perform your own calculations, because at ten days the difference between Alcohol, canisters, esbit and WG start looking different enough at the start and finish to become less important and more about the type of hike you are taking. That is early mountain climbs, or, later mountain climbs? Canoing then hiking, or, hiking then canoing? Even at ten days this has a pretty drastic influance on when you want the weight to change fastest. As Dan said, you can sort of choose when to carry less, even if it means a bit more to start with.
In every case up to ten days, alcohol is always the lightest weight for average carry weight...even out to 12 days, the most I bothered to check this time through. It also has the highest starting weight for ten days. (I use about 3oz/day average over ten days. Some will use less. 4 cups of water in the morning, 4 cups at night, including 15min simmer for cooking.) For short trips(2-4days) alcohol is always a bit lighter than the Jetboil. Duration does matter, but it is far less important than other things at ten days.
An example: Canisters are within 4oz at 12 days, average. But you need to carry about 1.75 pounds of food per day for twelve days. Or, about 20 pounds. I do not think 4 oz is all that noticable in a 32 pound pack weight. So, I am kind'a going out on a limb, and I will simply call them fairly equivalent at that range. (Water is not included, it always needs to be present.)
Volume and usability become more important than raw weight for durations of a week or more.
For me, overall volume is very important. I use the smaller 2200ci Murmur for up to 10 days. And the obsolete MiniPosa for up to 15 days. The compact SVEA and a 12oz bottle of fuel will last 12 days, a 16oz bottle is more than enough for 15days. I will note that WG only weighs .8oz per floz. Alcohol is slightly heavier, but only by a couple hundredths of an ounce. Canister gas *used* to be 4oz but I believe it is only about 3.88, nowdays. The volume of fuel and containers gets pretty high at 10 days. The SVEA and a 12oz bottle is about the smallest. Canisters are all about the same as alcohol requiring *about* the same volume as a 32oz bottle. 3-4oz canisters(or one 8oz can and one 4oz can) is lighter than a 32oz bottle of alcohol, though. But, you always carry the canisters. With a small plastic bottle, I can reduce volume as I go, but this is not important on the trail. Only the starting volume is considered. Your pack volume does not increase after that. COnsidering *just* volume for ten days out, I will bring the SVEA, as I do.
Usability can get devided into several categories: temperature, group size, blustery conditions found at altitude, personal preference, difficulty of use (setup, knock down chores,) durability, reliability, legal requirements. Probably some others I missed (off the top of my head.) Personal preference has a lot of factors to consider, alone. As an example: some value the "turn the knob and press the button" feature of a jetboil. Some don't mind the extra fiddling of measuring fuel, setting up a cone, and lighting an alcohol stove. Or, like me, filling, priming, and lighting a WG stove. Or, the fussing needed to get an Esbit tab out of the wrapper, setting up the stove and, especially, lighting the tab. There is no way to evaluate these factors, generally.
There is more to think about than raw weight when you do UL backpacking. So, I cannot say that any weight savings is worth it in combination with all else that is specific to your needs for your trip. What I will say is to evaluate all components before trying to answer your own question. To do that, you need a lot more information than a weight comparison. Asking is it worth it in this group is like putting a mouse on a cats paw and wondering if he will grab it. Light weight is ALWAYS worth it...