Any split in the trade pool is bad but it has to be balanced between that and simplicity for new traders whose first language may not be English, plus the ability to track items. We had the same discussion over 1.11 and 1.12 or (and the various .a .b etc sub sections). No going back in versions is simple. No going back except between x and y versions isn't. See how people have issues understanding vanilla to modded ok, not the other way (similarly HC to SC ok-ish, not the other way).
I'm trying to remember who did the last multi-dll (I'm pressed for time right now) but I'll try and dig that info out over the weekend.
I'm using 1.14d as my primary version and I can confirm that self-MP is still possible, and I believe that all mods permitted in the MP/trade pool should work with 1.14d, so I'm not sure what reason there is to use 1.13, unless you're using mods other than FAM in which case you'd have to separate those characters/stashes from the pool in any case. I'm personally using RWM and a glide wrapper with 1.14d and both work perfectly.
The only difference with self-MP is that since there's no longer a d2gfx.dll file as Blizzard consolidated it into Game.exe, you need a patched Game.exe file instead. I don't recall where I downloaded the one I'm using, and I'm not sure if it's available on any site that's permissible to link to, but I took a look at it since I'm not in the habit of trusting unknown executables and it looks like the exact same fix as the patched dll, just applied to the portion of the 1.14d Game.exe containing the relevant code that used to be part of d2gfx.dll. It's literally one byte different from the original - at offset 0xF562A, 0xEB is changed to 0x74. Anyone with a hex editor can make their own patched Game.exe by changing that one byte.
Unless I'm missing something, it seems like the only thing that doesn't work is version switching software, which is a convenience but isn't actually necessary to run 1.14 alongside other versions. If the lack of support from version switchers is what's keeping people on 1.13, I'd be willing to help develop a solution if it meant consolidating the pool. I know the author of Bliss says he has no plans to support 1.14, because he doesn't think there's any reason to upgrade, but it's open source and I don't think it would be too difficult of a feature for someone else to add. I don't think it should take much more than just adding some code to check if it's switching to/from 1.14, and if so, delete/restore the relevant dlls.
I know a lot of people using 1.13 don't see any reason to switch if it works for them, and if characters and items could move freely between 1.13 and 1.14 then I'd agree. But the way I see it is if we're all going to use the same version, the only other way to consolidate the pool, it's more feasible for it to be 1.14 than 1.13. I see a lot of people saying they're identical so there's no reason to upgrade, but that logic goes both ways. And in fact, while the gameplay might be the same, the compatibility fixes in 1.14 were necessary to keep a 16 year old game working well on modern systems, and there are people for whom 1.14 just runs better. Plus it's the default that you get if you download the installer from Blizzard instead of using a CD, and if you don't think that matters, just look at all the posts from people who have 1.14 and are having trouble downgrading.
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