A difference of 10 pts in a total that high cannot be conaidered a "clear line error". It may be that it was in error but who the fukk is supposed to know? If 5d is the only book someone plays at, they're not shopping lines.
Id say slippery slope here but I think it's well beyond that already. The precedent has been set quite some time ago. They're not going to pay even on the smallest of errors nevermind it having to be a clear line error.
But this is certainly rubbish.
We're talking about a line error of roughly 6%. And it's "clear"
complete bush league.