Then that makes Lore a skill that only one player ever needs and completely invalidates the other PCs having it. We generated the party with the random adventurers booklet so one of the pcs has a Wits of 5 and a Lore of 3 and two other characters have lore as well. They might as well not have it in that case.
All that's been discussed so far in the thread is quite useful. Responding to this particular point, even if you don't end up incorporating anyone else's advice but want to limit to 1 roll for the whole party (which happens in all kinds of cases, including group instances of sneaking and watching for ambushes, in this rules system): (1) the party isn't always all together or having exactly the same experience [also, see the poster's comment about lore rolls more related to one character's background] (2) Wits is
subject to damage, and that damage isn't necessarily going to be healed at a convenient time to make a Lore roll [and I typically have the party member roll who currently has the most dice for the roll].