That info came from the Vlide 'break on error' then print results. I use this to see DXF items:
(defun c:dxflist (/ e)
(cond ((setq e (car (entsel "\nPick something to see DXF data: ")))
(mapcar 'print (entget e '("*")))
(textscr)
)
)
(princ)
)
There is also DUMPALLPROPERTIES to be used in conjunction with get\setpropertyvalue
Not sure why your code gave odd result, I drew the 2 plines on a angle as a test in two directions, You are right I have been using pick an end for direction for like 30 years, you get used to it.
RIA waiting for you.