Originally Posted by JoeDiver
Thanks but I don't need a lesson in spring lines. I know what they're for and how to use them.
My point is his lack of need for them in his situation, and questioning why you recommended them. 4 dock line, 2 fore and 2 aft, are sufficient for deep inside a sheltered marina. A boat doesn't need 8 dock lines in that environment.
I am not sure if you know what spring lines are for. They prevent movement of the boat for and aft. Bow lines and stern lines are to prevent boats to move laterally. Remember that lines ONLY exert force along their long axis (you cannot push a rope). Of course, a bow line can have a fore-aft component but that is not what it is for and it is poor seamanship to rely on it.
I don't know the exact circumstances in that marina are but even if it is sheltered from the elements, I don't know how you can be sure that there are no waves from passing boats. I strongly feel that at least one after spring is needed to prevent the boat hitting the dock with the bow.