Does the MUTCD (or any other resource/agency) actually regulate (or just suggest) where sign poles go? This would include how far in advance of an intersection, how far off the road (somewhere within the ROW, before a ditch, etc), and other examples.
I have seen several examples of advance signage really far from an intersection, especially numbered-road sign assemblies you would normally see AT an intersection, as well as non-overhead BGSes way off the road to the point of not being applicable or readable.
I guess another issue that could be covered by this is trees/shrubs blocking the view of signs. I have seen both plant growth eventually getting in the way, and signs seemingly installed right behind a tree/shrub.
I know there isn't any heavy-handed government agency pounding their fists about this, but the almost lax examples I've seen look bad, and hopefully are just isolated situations and not a trend.
MUTCD gives guidelines such as minimum distances, but not absolute values. Example: https://mutcd.fhwa.dot.gov/htm/2009/part2/fig2a_04_longdesc.htm
Big John is correct.
There are minimum distances for sign separation. There are also minimum sign heights and other specifications on mounting. There are also minimum distances between the edge of pavement/traveled way and the sign pole (the "lateral offset") – interestingly, there does not appear to be any *maximum* distance for the lateral offset.
The MUTCD specifies these all these criteria starting at section 2A.16 Standardization of Location (https://mutcd.fhwa.dot.gov/htm/2009r1r2/part2/part2a.htm#section2A16) and dedicates the next few sections to sign location & mounting details.