Even though there was a thread about Maxima couple of weeks ago that touched on this subject, after the recent passing of George Harvey it's good to bring it up again.
Mr Harvey's leader design was, and is, the best there is for fishing the dry fly.
Stiff in the butt and taper and supple in the tip, it turns over well and still lets the fly float drag free through the drift.
Mr Harvey was big on the elimination of drag.
I believe George Harvey never fished lighter than 5x either.
I've tied leaders my own for years and I feel knowing and understanding leader design helps your general knowledge of the sport in much the same way as tying your own flies.
For more complicated compound leaders, I generally follow the formulas that came with my first tie kit 20 years ago, but for more simple designs I'll build my own to order.
For example;
Short nymphing leaders work well with a 50/25/25 (%) design
Long (12') dry fly leaders... 40/20/40
For bass bugs... 70/10/20
You can't get that out of a package
The simpler the outfit, the more skill it takes to manage it, and the more pleasure one gets in his achievements.
--- Horace Kephart