Yes Nigel buy, we purchase from people with quotas to fish, the rights to those quotas. By the same token foreign vessels could purchase quotas from British vessels to fish British waters.

I can guarantee you one thing, the trawler owners will take whichever option is more beneficial to them.

I agree. So if we can buy fishing quotas to fish in the waters of other states (if we need to with our expanded waters) is this legal?
If so, it makes a nonsense of your statement: when our fishing grounds are limited by not being part of the EU regulations we will only be able, legally, to fish within our own fishing grounds