This has been discussed to death on numerous lure and predator forums over the years, with polls on how many people have caught/found dead pike with lures in their mouths, as you do with bait traces, and people from both sides give valid arguments.
From having the initial stance of "if there's pike present, wire must be used" my outlook has softened somewhat, after a lot of deliberation, although my personal choice of material hasn't changed.. here's my tuppence worth.
Fluoro can be bitten through, fact! I've seen evidence of 140lb fluoro bitten clean through by a moderate fish and witnessed 20lb fc being bitten through by (literally) everyone I know who uses it for perch and zander.
The way I see it is that fc, and hard mono, is dangerous for any sort of pike leader or trace no matter what breaking strain.
Zander can bite through fc but it appears to be rare (probably to do with teeth density). Never found zander to be put off by wire but perhaps it might (a big might imho) have a softer feel to their mouths when dropshotting (can't see it personally after watching zander feed in a tank and seeing the angles they take and point of attack).
With single hook lures, like shads on jigheads, evidence from lure anglers suggests that pike can get rid of them in most cases. This is where I've softened my opinion and have conceded that it probably isn't a particularly big problem, especially if it's a barbless hook.
When a stinger treble is added then wire must always be used as the main leader and stinger. Whenever it comes to potentially leaving any treble in a pikes throat then fc is unsuitable imo, especially in the 20lb range which zander stingers would be, and down to 5 or 6lb fc for perch!
Saying that, I still use wire for everything from perch to pike and am of the opinion that I don't want to risk leaving anything in a fish if it's avoidable. Unless fishing for perch in a clear, shallow venue then I personally can't really see much use for fluoro in freshwater predator fishing.
One thing I would say is don't believe the hype. Youtube is full of people trying to make a name for themselves and their primary concern isn't fish welfare, and by advocating the use of fc and other, ethically debateable, practices/methods they see an opportunity to appear "on the cutting edge" of uk fishing. They ain't.
Sorry if I've waffled (this is actually the short version
) but it's a subject that hasn't got a definitive answer. No agreement has ever been made between fc and non-fc users and it never will. Consider the pro's and con's yourselves and make an informed, personal, decision.
btw, Anglian Water made a rule change last year which means any predator fishing must be done with a wire leader.
