No. I am curious about the instrument used. I chose this approach because:
- there is no decimal value greater than 12
- there is a decimal value of .10 and no others show signifigant digits
In either instance, the difference is negligible except for the calculation for OM-6h. The rest will be gobbled up by rounding anyway.
I guess one way to tell would be to calculate OM-6h and OM-6f using both methods and comparing the results with what we know about Martin's height.
I think what you are seeing is this.
Total stations are becoming standard equipment at crime scenes where there is a lot of spread out evidence to locate. My understanding is that SPD used one there.
The procedure would be to set up on a point that could be easily returned to if necessary, and could be counted on to stay in one place. The intersection of the edges of the sidewalk at the "tee" would be ideal for this.
Then a couple of permanent features would be located for reference purposes and to establish an orientation for the data set. In this case that would be the two building columns. (Only one is needful, the other is redundancy, and to facilitate re-establishing points at a later date without an instrument. More on that later)
Finally all of the locations of the various points of evidence would be recorded.
After having done this it is a simple matter to inverse between any two points in the data set and find out the distance and bearing between them.
It looks to me like they did this between each of the evidence locations and both building columns so that anyone with two measuring tapes could go back to the scene and re-construct the locations. No total station (and someone who knew how to use it) would be needed.
Civil and surveying distances in the U.S. are most commonly expressed in decimal feet. All of the total stations I've used in the past twenty years can be set to calculate and display in decimal feet or in metric, but I haven't seen one that uses feet and inches. Most surveyors and field engineers routinely convert between inches and decimal feet in their head if they need to. It isn't particularly hard with a bit of practice. Someone who can't probably can't use the hardware either.
It's not uncommon in situations which don't require high precision to keep the display precision for distance on a total station set to two decimal places when working in decimal feet, more than that clutters up the screen real estate, and tends to be wishful thinking anyway. I think that whoever hand drew that sketch was probably reading the distances off of the data collector they were using to inverse the points and just rounding to the nearest tenth in their head. (Hundredths ... roughly equal to eighths of an inch ... aren't particularly realistic or even useful in a situation like that.)
My guess is that the one measurement with a zero in the hundredths probably actually
had a zero in the hundredths, on the data collector display, and whoever was copying it just inadvertently wrote it down that way without thinking because they weren't actually rounding that one.