[BBKing]

I tend to steer a bit clear of running stuff on customer's equipment, since it immediately incurs a massive overhead of staff, which isn't the point of the exercise

I'd see it as partly to help the customer solve issues without ringing in (which annoys people, oddly), or to identify common problems, like offset frequency or upstream congestion - we could possibly even say we were aware of the issues and planning an upgrade on date X (ideally, although this is just me speaking, with a rebate on the bill until then). If you subsequently called into the tech support centre it's not impossible to have the results of any tests you've run presented to the guy on the phone so he can see e.g. at 9pm it was rubbish, even though it's fine next morning.

There's also the sheer nerd factor of patching into our sophisticated volcano lair monitoring and diagnostic systems...