[xs_tackle]

Pescador,
Interesting. I'm amazed at the many different ways this can be done. You have developed it in several special ways; and, I'll have to think about them.

I make double-walled topshots and leave a loop which uses about 16 inches of spectra. For 100+ # topshots, I generally try to make the double-walled part 5-6' long--plenty length for spectra to "grab" the mono w/o using a nylon sleeve or and w/o nicking the mono.(Maybe one day, I'll back off to 5' or even 4' of double-wall; but, I'm in no rush.) That generally works out to require about 14' 6" of spectra. Interestingly, it seems the outer leg almost always takes about 8" more spectra than the inner leg--maybe b/c that corresponds to the additional length consumed by the spectra being expanded to the additional diameter required to accommodate both the mono and the inner wall of spectra. Finally, I think my sequence of steps is different from any I've read before because I begin by inserting the mono into the shorter leg of the spectra and then "pull a loop" starting at the top of the other leg and then pull the mono side thru the loop so the longer leg inverts over the leg with mono in it. (For this step, imagine pulling a loop in a plain piece of spectra, then imagine that the spectra pulled thru--onto which the other spectra is inverted--already had mono inserted into it). I hit upon this only b/c I never managed to make the way described by Jerry (Snagged) to work w/o roughing up the line.