Don't get too hung up in trying to be too clever in drafting*.
Woody;
You simply need a ban on the removal of any fish, dead or alive, from any water within club XXX or YYY water authority's area without the fishery owner's** express permission in advance or (on public water) in accordance with the bag limits / size limits prescribed.
The fishery owner's permission is also of course subject to any bag limits / size limits established by bye law.
So, for example, in the Thames area it's no more than two fish of the sizes above those in the Schedule to the bye laws and no fishery owner within the Thames area can lawfully authorise more than that.
As we have already canvassed ad nauseum the fishery owner can limit it further to say one fish of larger than specified size, or refuse permission altogether.
These rules relate to the removal of fish from the water. There is therefore no need for an exception for pike live baits - they're NOT being removed from the water !
Under present fish movement rules no live fish can be taken to a water for use as live bait. They have to be caught from the water you intend to use them in. Retaining them in a keep net for later use or release if not used is not removing them from the water.
Catching fish one day and taking them away for use the next or another day is plainly a possible loophole but it isn't in reality, as any fish caught and retained live or killed for later use as a bait on some other occasion is still limited by the fishery owner's permission, and in turn further limited by the bye law limits, as above.
So to stick to the Thames example anyone with more than two fish alive or dead is plainly caught.
All of the above is jolly interesting etc, but the fact is that it is already the state of the law as it stands !.
No further legislation is needed, simply enforcement of what we have. Enforcement is the key, without it the rest is just words in the wind.
And I think I have already been round that particular Mulberry bush often enough not to be interested in restarting the debate, so please don't bother, I shan't be feeding the Trolls again for a while thank you.
* That problem bedevils modern statutes and statutory instruments, pages and pages and pages of reams of self-reinforcing definitions and sub-definitions that only serve to confuse, obscure and make unintelligible instead of clear. Have a look at some 17th century statutes (and judgments). Beautiful in their economy, simplicity and clarity of wording.
** a loose and non-technical phrase intended to refer to the owner, possessor, person club or body in control of the exercise of the fishing rights in any relevant piece of water.