There is good money in being a useless twat with a laptop.
It really is a win/win situation for the franchise to employ them.
Seems all the really good guys set up an indy these days
Same goes for the AA and RAC, roadside have little mechanical experience and are just pumped up software jockies.
If you can see the level senders on the display, and they are not right, then its pretty obvious to me.
The pair are averaged to allow for street parking and slop. I expect your old binacle (if low miles) would end up a useful spare for a dealership ... aghem....
Steve