Shouldn't it be target line and not source line for an elevation instruction? You are applying this elevation to the target.
This is not really mission critical is it ?
These instructions like VPI, Elevation and Grade are al the same and only apply to one line - whether that is the Source or the Target is a debate of course but I think the logic is that line 1 is source and line 2 is target and because there is no line 2 it is the Source line.
Not at all.
I agree still works perfectly. More of a consistency thing.
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