Progs are somewhat biased in neglecting the combined possibilities that
1 the fence was placed there for a reason
2 it was well optimized for the reason
3 the reason is still valid
4 it is still well optimized
....but the NRs are much more biased, because they are assuming that all of 1..4 are correct. The odds are strongly in favour of the prog assumption that one went wrong.
Progs are somewhat biased in neglecting the combined possibilities that
1 the fence was placed there for a reason
2 it was well optimized for the reason
3 the reason is still valid
4 it is still well optimized
....but the NRs are much more biased, because they are assuming that all of 1..4 are correct. The odds are strongly in favour of the prog assumption that one went wrong.