We got this in our Reddit inbox from a fellow angler at /r/flyfishing today and wanted to share (reproduced here with their permission):
"The ideal butt section is 5x flyline weight. Rowland says 50# test but that's for a 10wt. Most salt anglers use an 8wt and should be using 40# test. 50 will kill momentum and result in less leader turnover.
A 3-piece leader turns over every bit as well as his recommended 4-piece, while requiring fewer knots and fewer varieties of leader material. 6' of 40# to 3' of 30# to 1.5' of tippet is all you need.
Slim Beauty knots (without doubling the smaller line) are far stronger than Blood Knots, and far more streamlined (i.e. Less likely to snag debris or catch in your rod guides) than uni-to-uni knots.
Chapstick is a superior knot lubricant, esp for heavier fluoro lines."