exactly, double techstopping would make sense in a 1946-2030 game, where in the beginning you can only choose from C46, DC3 and maybe some 10 seaters. So that your range is actually limited to under 1000NM which means you need to tech (and double tech-stop) planes to actually reach most of the destinations at such early dates.
Though I generally tend to not using tech stopping at all, as it usually makes things complicated upon fleet renewals (complete closure and re-opening of routes, big time differences between tech-stop and non-tech-stop routes, etc.) I only use them when not otherly possible (e.g. in JetAge games with DC-8 for the 6000NM+ routes where I know I will never have 744 or 772ER/LR available to actually fly the routes nonstop, or in DotM games using 744 for the 8000-10000NM routes with a techie because 77L won't be out before the end) This is all mostly caused due to the calculation on which planes will come and which will not before the end of the game. A long game world should also fix that, as players would look forward to a more long term planning which will also effect route-building.