Never had a zone bust, but the times I have come close were due to wind calculation errors or different wind to what I had planned for altogether. The relevant controller advised that my heading took me into their airspace so I diverted. If an ATCO sees somebody bumbling towards their CAS, they should shout. Obviously, this is no good without the pilot being tuned in. Never forget the 6 P's! If your flying close to CTA, call them on the radio. If your not intending to go close to the zone, at least have their frequency on standby. Tune in and ask if you think you might be a little closer than planned. IMHO, pilot awareness and planning are the key factors in zone busts.
With regards to GPS training, what about a couple optional hours on top of a PPL, like with a night rating? GPS may replace older forms of navigation, in which case the methods they replace will be taken off the syllabus, keeping it at 45 hours. Of course costs probably would go up, whatever happens, but a required rating to use a GPS would reduce the number of GPS blunders.
Though having said that I haven't gone electric yet, and so far have done fine without. Some people are just idiots (no offence anybody
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