Extend from a 3/4 Tag
I was trying to use "Extend" from a 3/4 tag the line position, and I am used to seeing the centers extend to the ends to make a line. The way that you have it, the centers go behind the ends. Are we wrong when we tell the dancers, "Extend to the girls (boys) to make a line?
From a 3/4 Tag, Extend ends in a Full Tag (completed DPT).
Extend means move to the next fractional tag position.
Hence a 3/4 Tag, ends in a Full Tag. See the diagrams at
http://www.ceder.net/def/extend.php
If you put helper words in there (e.g., "to make a Line"),
then you're directionally calling, and whatever you can get away with is fine.