I'm certainly not sure why they are there - history perhaps or this tabletop thing you all keep banging on about. I'm not sure why CON or WIT is there for either.
Probably for the P&P-RPG feeling, but because how talking, shopping & inventory management work, they are more bothersome than enlarging the experience. In a Pen & Paper session the guy with most Charme could always show up and take the lead in conversation or at least you could delay the talk.
I don't know what the word synergy means in this context (or any other context tbh).
Synergy means, that two things are working hand in hand. Like Endarire said, if you have barter and persuasion the prices will be cheaper than with only barter. If you had thievery, lucky find and loremaster you could lockpick a chest, loot it and identify the findings all at once, but good luck with getting enough points for that with out having to change tons of rings and other stuff all the time.
Bollocks. Loremaster is shared. EDIT: Isn't it?
As far as I remember in the first it wasn't. But as I tested now, in the second it seems to be shared. At least if you play all characters alone. Can't test if it works in coop aswell like that. Never tested. I was used to it not being shared like all social skills.
If you mean the inventory management is shit then I agree. It is even worse than DOS EE.
You forgot to mention that you can't even hide the shit you just sold them or sort it by date, weight or anything else.
Whoever made DOS2 inventory management even worse than DOS EE (which was terrible) should be offered a beer and shown the door.
It's one of my core issues with the second game. They put in a lot new stuff, with hardly bothering about some of the core flaws of the first game or even making them worse.
At least with the last patch they made it a bit better.