Interesting how maintenance is seen as such an important part of sailing. Whilst I fully understand the concept of knowing your boat really well especially if youíre doing long passages and keeping it in a proper functional state, I think of other things that are more important. Hereís a good example (for me anyway).
On our return passage from the tropics last year, about two days out, I ran the engine to get some hot water for the shower. The overheat buzzer came on and the temp gauge showed high coolant temp. Knowing that I had installed a new raw water impeller before the start of the cruise (maybe 35hrs of engine time), I started visualising all the other scenarios that would cause this. All of them were too large to worry about at sea so we sailed the next five days without using the engine, including strapping the dink alongside and using the outboard to get us onto the customs dock in NZ.
Much more important on the passage was the weather and what is was likely to do next, what we were going to eat, our course home, the sea state, how much drinking water we had left, other vessels in our area, sailing the boat efficiently, carrying a safe amount of sail, keeping family appraised of our position, whoís getting seasick or tired, the state of our batteries, itís a long list.
Mechanical problems were waaaay down the list in order of importance. I could comfortably lose most of my mechanical systems and still get home safely as long as the aforementioned details are taken care of. As long as the boat is not seriously leaking and the rig stays up, Iím good to go. Interestingly, one mechanical thing stands out - at least one of the toilets must keep working
Back to the original question: do these skills get rusty? Sure they do, the same way that riding a bicycle does. But itís a short trip back to full competency and not something that I actually think about.