Alan...a big eel is capable of making a mess of anything mate, let alone a rig. It seems to be the smaller eels that make a tangled heap out of your carefully tied rigs, they seem to thrash about a lot more than a big one does, and generally twist themselves up in knots around your traces, whereas a big mother just pulls. And pulls.
As for unhooking eels, the best way is... carefully.
Keep your eyes open on the techniques page for another article on that very subject, but in the meantime, don't be tempted to wrap them in newspaper, sacking, hand cloths or whatever, that just destroys the eel's natural body slime.
If the fish has swallowed the hook, then just cut the line near the eel's mouth, it will soon get rid of it in it's own way, and very quickly.
An eel can be calmed down enough to remove the hook by simply laying it on it's back and stroking it down the body a few times, that seems to send the eel into some sort of temporary trance-like state....the time this lasts will vary according to the individual fish, but you should have ample time to remove the hook before the fish wakes up again.
Try it next time you catch an eel...it does work.
Rich
) It can work on perch too, turn them upside down and they are quiet for a short while.