Handling Issues Options

[GT4WRC]

Over the last few days, there has been a certain 'vagueness' about the handling on my car. Seemed to start after I fitted the Cusco lower brace. Initially put it down to the alignment needing re-doing, but gradually got worse, making me think something else was causing the problem.
Finally had the time to get the car up on a hoist this morning for a good look and a 'spanner check'. Upon closer inspection, the passenger side superstrut figure of 8 arm caught my attention. The split pin and locking cap had come off and the nut was nice and loose. No wonder the car felt awful to drive! Odd thing is that the figure of 8 arm was replaced nearly a year ago and hadn't been touched since. The fact that a split pin could simply 'vanish' has me completely stumped At least it was an easy fix and the car is no much nicer to drive. But the fact that a split pin can simply disappear like that is a bit worrying!
Gary