Is it possible to add/replace walk styles?

I know you can 'change' the walk style of a pre-made sim to another 'default' walk style in CAS. I haven't seen any mods that change a walk-style, however. I feel as though that would be insanely complicated if it can be done - every walk style is created to fit into every piece of code of the current and future game and to work around and with every object and scenario.
If you were to include a cane (as CAS) then you'd have to think about scenarios that do not include the need of a cane (i.e; eating, drinking, showering, etc.). And, if you were to include a cane as an object, you'd have to code that endlessly. Where will it be put down? The inventory? Or right beside the owner? How will it work with daily situations, communication and contact between different sims?
I'd say that that in itself is a tough job, disregarding a moving 'vehicle' in a way.
I have been told that TS4 is much harder to code than TS/TS2. I would by no means want to stir you away from trying to do this, but I'd have no clue how you could even start. I haven't really seen any experienced TS4 modders even attempt this, parting from a walk-animation used in Pose Player.

I think if we could implement canes with a walk style, we'd just have to be okay with them clipping through door frames, and they'd just disappear whenever the sim wasn't using that walk style (ie, they switch to the tired or have to pee walk styles, or just plain are standing still). Then again, I feel like the way walk styles work, it wouldn't be possible to "attach" an object to the walk style itself, so I doubt it would be possible regardless.

Yeah, that's what I was thinking. Hopefully, had Sims 5 come out, it will be similar to TS/TS2 in modding, which would be much easier.