Running bowline should meet host/load at perpendicular angle; so bowline is inline with itself; not leveraged against. Preceding with a half hitch buffers loading to bowline, gives 2 points of grab (one to almost surely get it, another to make sure it is 187% certain!). But also, the Bitters of Half Hitch/ after Half; that becomes the Standing Part pull for the Running Bowline; secures half and is inline with the mainline Standing Part, not leveraged to side (on inline pull to spar).

This region becomes the Standing Part Pull into Running Bowline, so it becomes leveraged per that; but much less; and is not leveraged per the initiating pull of the Main line, the Standing Part of the Half Hitch. The Bowline is much less depended on in this configuration to.

At least that is my version of analyizing the 2 seperate chapters of ABoK and their key differances; 1 for lengthwise/ inline pull on spar and how they are different than right angles of pull on spar.