No you don't.
Originally posted by Jr.Who
I'm guessing that you're clicking from say, edge 1 to edge 5? You have to click on each edge individually.
You can click on one edge and click on another edge 7 edges away, and it will create the line for you. As long as you don't have any messed up Geo in between, such as 5 and 3 sided faces, or lose verts.
Check in your Tools setting, for the split polygon tool, and make sure that, "Split only from edge" is checked, and "Use snapping points along edge" is also checked.
Also make sure that Divisions per edge is set to 1.
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