Not necessarily!, it all depends on your personal preference.
There's 3 basic ways of sorting tube flee's to yer 'ook!.
1, Is the std extension tubing of silicon/flexible rubber/plastic mounted on the rear of the tube, the nylon passes through the tube and extension, the hook is tied to that and then pushed into the flexible tube extension which holds the hook in place, but usually separates when a fish is hooked and being played.
2,The tube itself is wide enough to accept the hook eye and knot being pushed up inside it- quite popular amongst those who self tie in the Scandi stylee, as effective as the former method.
3, The free swinging tube, simply the tube is threaded up the line, the tube is tied on and allowed to sit at the base of the tube.There are a few variations on this in that you can slide a small bit of narrow diameter silicon(pole fishing silicon) onto the hook, then slide it over the knot and hook eye to protect it from the tube constantly banging on it, or there are "propellor" tubes which do exactly the same, merely protect the knot at the hook eye.
I favour the former two methods, extension tube for metal and the std, tying of tube flee's, the second I favour with small and tiny tubes where I'm looking for a smaller presentation all over usually scandi stylee wings.
I prefer a hook held in place for a very simple reason, as I use Terrible's where it's acceptable to do so, I rig them in keel fashion as this dictates how the tube will fish.Most terrible's are made from a single bit of wire with two points fashioned, the 3rd point is a separate bit of wire braised on top.Align the tube with the single braised point uppermost when you fix it into the flee as this is how the tube will fish in the water, double points down, single point up.
Obviously hooks with a large single wing tied on top of the tube may not be affected to the same degree as a conventionally tied tube, but it does work, self tied tubes with a long top Scandi wing can fish off to one side or indeed upside down. Align the hooks with the wing and it will fish level the right way up.
Trust me it works!.
Pedro.