I have seen where a surveyed corner was 50' off from the GPS coordinates.
Fence lines out west more often than not are 30-60 yards off of where OnX and/or GPS says they should be, let alone 50 feet. I am guessing GPS would show the "correct" location vs what was determined by a Gunter's chain 150 years ago, but I am sure that could be contested in court if a citation was issued.
Variations could also be from your GPS being set to WGS84 and the mapping data being based on NAD83, or vice versa....Lots of possibilities when it comes to that kind of thing.
Too many relying on GPS to flirt with boundaries do not understand your last sentence. IME also why some report "accuracy" issues when comparing devices.
Agreed. I haven't noticed the WGS84 and NAD83 to be 50 yards off....more like 10-15 yards in most cases but with the perfect storm of software incompatibility, thrown in with poor signal strength from cloud cover/canyons or cheaper devices, a guy could be pretty far off their mark. Best to be used as a general reference only.
It is nice to know that if a watershed divide is a unit boundary, even if the GPS is off by 100+ yards you know that the main, huge ridge right in front of you is the true unit boundary. Checkerboarded areas with lots of seemingly random allotment fences can be a nightmare but if the property overlay shows the "next" fence 50-100 yards over there is the property boundary, it is pretty nice to have too. I think these types of instances are where this technology is most useful.
