Hey Josh,
(CC to devel)
The pentool bug is a good one :), yep I only thought of using the node tool for editting paths doh!
Stacking is definitely planned. But... at this moment it will not help you a lot. The problem is that the path-along-path effect has its inputs switched around:
path-along-path: svgd input = path to put something along (can only be one path, probably cannot contain gaps or anything)
                        parameter input = path to put along the other path
The stacking will work like this (because this is simple to implement [1]): output of one effect goes to the *svgd input* of the next one. As you can see, this will not function as desired for stacking curve stitching and path-along-path.
"So why is path-along-path made this way? It is also not handy for applying it to groups!" The problem now is that only the svgd input can be editted on-canvas. The parameter paths cannot. So imagine having that fish bend along a curve, and then not being able to nicely edit that curve :S
On-canvas editting of path parameters has very high priority on my list, but it is not so easy. This curve stitching thing was really easy to implement (just look at the code), and it seemed fun :-)
[1] probably I should also add a method to pass the result of an effect as path parameter; it will start looking like the whole filter thing then. Perhaps it is better to make the SVG2 vector effects first.

From: Josh Andler [mailto:scislac@gmail.com]
Sent: donderdag 30 augustus 2007 2:57
To: Engelen, J.B.C. (Johan)
Subject: Re: Curve Stitching first steps

this is beyond cool... is it in the plans to stack LPEs at some point? Just wondering. :)  Anyway, this is basically effect lines (with the exception of being able to "path on path" with the lines)! Woohoo! And it seems like this should really be helpful with one project in particular that I have occasionally thought of working on. I'll have to play with it a bit.

1 bug I found - on the object that has the two 2 node lines, select it and change to the pen tool. You'll see that it shows the ends of all the "stitch" lines as if they can be worked with using that tool (which doesn't work). 
1 easy to reproduce crash - with either stitched object, use the node tool and select one of the two subpaths and hit Shift+R. Boom! (shift+r reverses paths)

On 8/29/07, J.B.C.Engelen@ewi.utwente.nl <J.B.C.Engelen@ewi.utwente.nl> wrote:
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