What is your typical tidal swing? How is the line to the forward port piling tied off. What is the length of the line from that pole to the cleat?
As I see it, all the lines except that port fwd line are tied off to a point that moves up and down with the tide. The port fwd line on the other hand probably doesn't and could be an issue if too short.
Have you experienced a really taut condition on the line?
The drawing doesn't show the correct angle of the bow lines and doesn't show the sag in any of the lines.
yep the port bow line is the only one not floating. Everything else goes up and down with the tide. You are correct there has to be enough slack in the lines for outgoing and low tide (bow faces outgoing tide). The lines are all set the right length with the eye to the boat. There is never a case where the bow and stern lines are both tight. (except for loading, I haul in the center dock line and giv it a wrap to hold the stern tight to the dock.)
The port bow line holds the
bow from ever touching the dock. The stbd bow line prevents the bow from ever touching the port pole. They both prevent the stern from moving too far toward the dock.
The tension of the sliding spring line isn't much but it doesn't take much to hold a floating boat off the dock.
Docking stern-in makes loading and cleaning an express much easier. My dock has a crazy current in both directions. I find that backing in gives much better control because the stern immediately follows the motors. In fwd, it takes space to turn the bow. In a crazy current, between two rows of docks, you have no space