Warpspeed to Amsteel end-to-end splice

[AaronD]

Maybe this is a silly question, but I'll ask anyway. Is it possible to splice Amsteel to Warpspeed (or similar core-dependent lines) end-to-end?

I have a nice nearly brand-new length of Warpspeed, but decided to do a 2:1 halyard (to get good tension on a the furling line for a code zero). So now I need another 20 feet or so. And no matter what I try, I can't make the stuff stretch I guess that is why we pay the big money for high-tech lines...

Specifically, I'd be interested in splicing 1/4" Warpspeed, which I think may be more difficult to work with than larger diameters (I don't have experience with anything larger, but I can confirm that 1/4" is a pain).

If it's possible, would 3/16" Amsteel be the appropriate dimension to approximately match the core of 1/4" Warpspeed (and fit back into the cover)?

I would imagine the process something like:
--Milk back ~5 feet of the Warpspeed cover
--Trim off some of the Warpspeed core (maybe a foot or so? Enough that we can later milk the cover back over crossover point)
--Splice the core to the Amsteel using Samson's 12-Strand Class II splice (it calls for 7 fid lengths, or 36.75 inches for 1/4")
--Milk the cover back over the crossover
--Stitch / whip

The end product would (I think) be similar to Warpspeed with a stripped end. Naturally, this isn't a process Samson will want to document, since they'd prefer I buy more Warpspeed and strip the cover, instead of adding Amsteel at ~1/2 the cost per foot.

I suppose an alternative would be a splice from Sta Set or other dacron double-braid to Warpspeed, at the tail of the line - it wouldn't even need the full strength of the dacron, since that part of the line would only need to hoist the weight of the sail, and would be coiled past the clutch before the halyard was under tension. It would just have to be a smooth enough transition to pass through the clutch (mine are sized for 1/4" - 5/16" line, so a small lump at the crossover would probably be fine for me, although that might not be a general solution).