Food for Thought, i.e. Confusing

[gates_cliff]

I was reading through Cruisers Forum and ran across the following:

You can tie up to hold the boat in one place by having no slack in the lines, but use as much line as you can. This is accomplished by having more horizontal than vertical deployment. When you are done, the vertical distance from the boat's cleat to the dock should be about 25% of the horizontal distance between the boat and dock cleats. This allows for the boat to move up and down, but limits horizontal movement.

Maybe (very likely) I just don't think in the abstract but can anybody explain or comment?

[tjr818]

I think it means that the writer was being paid by the word.
My take is that IF YOU ARE IN A SLIP and YOU CAN TIE UP TO BOTH SIDES, you can tie the lines tight to limit horizontal movement, but that also restricts any vertical movement SO IF THE DOCK ARE NOT FLOATING DOCKS, you should leave enough line for some vertical movement. Attention Bay of Fundy boaters!

[Neil Gordon]

Just draw some right triangles and label the corners a, b, and c. Let "a" be the pointy and and make that the cleat on the dock. "b" is the 90 degree angle and also the cleat on the boat at low tide. "c" is the cleat on the boat at high tide.

Tie up at high tide and your dock line is a-c, which is the longest side of the triangle. At low tide, the dock line is a-b, which is shorter.

A couple of tries with long, flatter triangles vs. shorter, higher triangles will illustrate the point.

(I got a B in geometry.)

[mgphl52]

Use long dock lines.
Attach bow lines to pilings/cleats aft of the stern.
Attach stern lines to pilings/cleats forward of the bow.
The boat can now rise and fall some distance with little side-to-side movement.

[gates_cliff]

Mike, Kind of how I look at it!