The core idea behind this post is this: in most cases, it is better to have something that doesn't look right, but does its job, than something that might look better, but fails. (The function of the object or system may be decoration, in which case there is no distinction to be made.)
Swordsmanship offers many concrete examples of this general idea.
For many rapier students, the hand position for the guard seconda is difficult.
So the first question to ask is, what is seconda for?
At this level, it has only one function. To close the outside line. So let's get that line as closed as possible, with a super-stable support system for the sword.
Nothing is getting through Janne's guard now! But it is not really seconda, is it? It is way too wide, and uses both hands. So we take the thing that works, and adapt it bit by bit to its proper form. First, only one hand.
Then the hard bit: gradually develop the flexibility of elbow and wrist until the sword comes towards its proper place, without the sword slipping around in your grip:
They key is to keep checking that the position is still firmly closing the line; all too often beginners will sacrifice its function for the sake of getting the hand in closer to the centre line. If the guard is supposed to be held like so, according to the instructions in the manual (eg Capoferro's Gran Simulacro), then one should work towards that position, once its function is understood.
As in swordsmanship, so in life. Function first, then form: form follows function. Which is why, when teaching form, I always start with applications, then string them together into the form. Form is by definition correct only when it fulfils its function.
If it looks good, that's a bonus.
You can read more about rapier forms here.
(with thanks to Janne Högdahl, whose seconda is pretty good these days.)