Jim, If you can tie a clinch knot you should be able to tie the Rivers Inlet knot, just double the line up.
Whats the point of using the same knot or line for three years. If I were a guide I don't think I would take a chance on looking foolish to a customer when a knot or line breaks on a fish of a lifetime. Line is cheap and knots are easy to tie. How does he know the three year old knots and line are as strong as ever?