>>782379No mate you don't understand
You can carry pretty much ANYTHING bar a very small list of knives provided you have a valid reason. innawoods is generally regarded as a good reason, as is fishing and work use. Having a machete to cut the crusts off your sarnies is not seen as a good reason. Understanding the legislation and it's limitations means you can argue back very successfully if you do ever get stopped (I have), however it's very unlikely you'll ever get hassled in an /out/ situation. Do you really think the fuzz are going to be out on a hillside doing checks of random people's backpacks for knives or are they going to be in a town dealing with pissed up yobs/ racking up people's speeding fines on a motor way?
You can carry a knife with a blade of 3" or less without reason ( aside from a certain few places like court houses and schools) provided the blade does not lock ( so slip joints and friction folders are go-go-go)
There is no legislation currently in writing or being lobbied that restricts assisted openers, flippers or one handed opening knives. There have however been problems with import where border force has been hammering any folding as a gravity knife and trying to get them to open with a wrist flick. Most UK knife bros now will tell a foreign seller to tighten up the pivot screw of the knife to the point of being non opening just to get it though the postal system.
Anything else...?