Does the spokesperson matter?

[Thumper]

Does it matter which character does the initial contact in coversations, or are social skills like diplomacy "distributed" to the entire group? I've noticed that vis a vis appraise, it doesn't matter which character I use (the bard with appraise 11 or the fighter with zero), I get the same discount.
How important is the spokesperson in general?

[Galuf the Dwarf]

It does matter who does the talking. The person who has the skill points has it for themself and themself only. Appraise and Survival work for the entire group, but not the dialogue skills.

In general, the spokesperson is VERY important. Numerous quest results rely on a certain numbers of skill points that a character speaking to an NPC has.