One other thing to keep in mind is that track is not a static thing. Gauge at various points can change with temperature. Take a perfectly gauged track at 40 deg. with normal gaps at the joints and then look at it again when the temp. hits 95 or so. The gaps will be completely closed and very likely you will see some minor sun kinks. The same holds true for switches. I've noticed at least 2 of our switches at SVRy that experience a marked widening of the point gap on exptremely hot days, but close up to 0 gap in cooler weather. About all I think you can do with kind of stuff is to be vigilant to look for things that can develope to cause a problem.