My comment was about overcapacity on the cross channel route, and I have never considered Newcastle a cross channel port.
I know nothing about capacity on the Newcastle/Holland route, and bow to your superior knowledge here. However, as the Rosyth ferry ran to Belgium, landing some 100 miles DFDS's terminal in Holland I am not entirely convinced that the two routes competed directly.
My understanding, gained, I must admit, entirely from the press and television rather than personal knowledge, was that DFDS closed the Rosyth operation not because of overcapacity but to save money on port fees, fuelled by a little pique because the Scottish government would not give them quite as large a subsidy as they were hoping for.
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