I recall the Lockheed Electra L188
A useful widget - the detailed system memory is a tad faded now but the basics were that we checked the numbers on taxi. Weight was reasonably accurate and each aircraft had a reasonably constant CG error which could be allowed for.
More than a few occasions where the system picked up loading errors - generally these were the result either of weighbridge defects existing as the cans were rolled across or cans which were not entirely on the weighbridge and part supported on the edge frame. I vaguely recall one problem we picked up where there was a bit of FOD in the weighbridge causing a repeatable error in the weigh figures.
The F/O, religiously, checked off the can tags against the loadsheet summary page .. very occasionally, can loading order errors were detected.
To give credit where credit was due, the freightshed guys and gals were pretty good and made very few errors. Flightcrew checks and balances were a good foil to shed errors and the operation, overall, went very well.
Far better to delay the flight and fix whatever at the shed rather than finding out about the problem during rotation ..
The most exciting example of this (and I can't recall whether it was on the Goose or one of the 727 freighters, although I think the former) .. a pond of water, on rotation, found its way into the hell hole and all went dark .. in the middle of the night. Apparently caused the crew a few concerns during the following 10-15 minutes or so while they sorted it out and got the aircraft back onto the ground.
Wonderful times ..