I'm building a 10' 9wt. Rainshadow for SW fishing. What problem, if any, would occur by going from a 16-stripper to a 6-snake rather than a 12-stripper to a 6-snake? There is an 18 and 25 following the 16 or 12, whatever the case may be.

I don't understand what you mean by an "18 and 25." Surely you aren't using a #25 guide ring for a stripping guide?

You can drop from a 16 to a snake just as easily as you can from a 12. I would hope you'd be using a 16 for your stripping guide, however, followed by the 12 or a 10 and then dropping into the running guides.

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I have been building some rods based on Ken Abrames rod designs. I have found that these set ups work wonderfully on the NE coast using 9-11 weight lines on less than fast 10' 6" rods. I am, however, open to what is inefficient about this type of set up. How would you set up a 10' 9wt using 9-11 wt lines with lots of loops and knots throughout the leader?

Any knot that will pass through your tip top, will easily pass through a #16 stripping guide. I've never found any advantage in going bigger and bigger on the stipping guide. The limiting factor pertaining to knots and such is the smallest guide on the rod, not the stripper.

About all you can do it try it both ways and see which works best. If you can't tell any difference, I'd use the set-up with the smaller guides as having less weight, it will be the more efficient set up.

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