In reply to Neil Williams:
No necessarily so. Reading Cotswolds certainly used to be staffed by several members of Reading Uni mountaineering club during term time and during holidays by locals that were away at other Uni mountaineering clubs.
That said, you will find that weekend staff don't tend to be the best trained, due to time constraints - staff that work during the week will have more time to sit down and go through the manuals and have a play with things. They are also the ones that are more likely to have had direct training from the manufacturer's reps, who visit stores Monday to Friday. Even then, they won't have the room to get all the tents out and put every one of them up, especially the family size ones. Cotswolds have run out of hours evening training and even done weekends away testing gear, such as tents, but you won't get all staff to all sessions. Note also seasonal changes - it takes a bit of time to get to grips with the new winter stock, for example.
I agree that staff shouldn't try and bluff their way through - if you don't know, refer the customer to someone who does and then stick around to learn for next time