After doing some drywall repair with the switch plate off I got a fair amount of dust in the light switch box, apparently enough to cause the the lights to flicker and the switch to make a ticking sound.
I thoroughly sucked out the box with my shop vac thus curing the symptom.
Question is, is this enough or should I replace the involved switch altogether?
If the wires were just pushed into the holes at the back of teh switch unit, it would be better if they were redone by being screwed on. There is almost no way that screwed on or clamped on wires would be impaired by dust.
Flickering lights generally means a poor connection.
If the switch works OK now I would not bother replacing it altogether.
Always flip a switch all the way up or down. Playing with it by holding it halfway creates a loose connection effect that can in turn damage the switch and make flickering happen all the time.