Link:
When I divide (1/60)/60 (one degree divided by 60 minutes divided by 60 seconds), I get 0.000277, which is more than 0.0001, so the four decimal places should be more precise than the degrees, minutes, seconds. In the US, typically the property lines are given lengths to two decimal places of a foot, so the lack of accuracy may be more an issue of the lengths rather than the angles. (And in the surveys I receive of an existing house on a lot, the building perimeter and distances to the property lines are to one decimal place of a foot, which is a bit more than an inch.) On anything other than a rectangular lot, I can never get the property line perimeter to close (you gotta zoom way in), I think the surveyors geometric description is just not that fine.
Plus, you've got that whole thing about the earth being curved
😉.
David