> > - Expressing positions as rectangular coordinates in the Texas Coordinate System facilitates checking and calculations from bearings and distances expressed in the same system.
>
> That's the same thing I already stated regarding inverses and translations.
Actually, not. If you think about how a surveyor would generate coordinates for a boundary with, say 200 courses, you'll appreciate the merit of being able to compare coordinates directly after manual entry of the 400 calls and the nearly inevitable hunt for blunders.
While I just provide the coordinates of all the points in the Texas Coordinate System in OCR-legible form, I understand that many surveyors are uncomfortable reporting the coordinates of more than a few points. Those tend to be a time-waster to digitize.
> You don't consider a 2°-3° mapping angle from North to be a distortion?
No, obviously not when the projection is conformal. If you're worried about adjusting your compass, you should realize that you can adjust it to indicate grid North about as accurately as true North.
> The fact that a CSF has to be considered at all is bothersome as evidenced by all of the techniques (proper and otherwise) which are employed to overcome them.
So, it takes a land surveyor, does it? Okay, that's obviously too difficult for the average lay person. :>
> I didn't post the question to convince you, Kent.
No, I read it as a cry for help.
State Plane Coordinates are Alive and Well
> with regard to boundary surveys, I invite you to read and understand a real live example
Yes, I believe I've examined that example before. The important failing of ECEF coordinates for cadastral use is that (unless air rights are involved) points lying in the same plumb line are considered to be in the same position for the purposes of boundary definition. In other words, a monument that is replaced in a road fill 10 feet above a position where the corner was originally established is considered to mark the identical corner.
When plane coordinates such as the SPCS are used, the fact that the replacement is essentially in the identical position is readily determined by inspection by comparing N and E values to those of the original corner. This cannot be done without laborious calculations or computer aids when ECEF coordinates are used because every point along the plumb line over the corner will have different coordinates.
That same problem would carry through when a surveyor is either :
(a) calculating the positions of corners from historical surveys where the elevations are only generally known,
(b) calculating coordinates of corners to be monumented on the ground at some elevation that is whatever it is, or
(c) expressing the positions of calculated points of indeterminate elevation.
In all three cases using ECEF coordinates for the tasks is more of a problem than a solution.
State Plane Coordinates are Obsolete
Many of us don't work in 2d. Our customers require our deliverables to be in georeferenced coordinate systems and our heights to be in a recognized datum. Surveyors produce mapping products in local, regional and sometimes statewide coordinate systems. State Plane cooridinates may not be obsolete but they certainly no longer served the purpose for which they were designed. They were designed with the assumption that 1:10000 would be good enough for the applications for which they were used. There was no intention that the end user would have to consider or apply scaling. GIS has little use for state plane because the mapping needs are either too large or too small (statewide or local county). Our state agencies use 1 UTM zone for statewide mapping. Our DOT has committed to georeferenced mapping in about a dozen LDP zones that will be defined in the state GIS systems. So while I appreciate the local XYZ differential tangent plane systems for very local 2d mapping can only see challanges for regional 3d or statewide mapping using it.