Treshold Signature Implementation ?

[Nicolas Dorier]

Is there any implementation of Treshold Signatures somewhere out here ? (http://www.cs.princeton.edu/~stevenag/bitcoin_threshold_signatures.pdf)
I intend to include that in NBitcoin, but would prefer not starting from scratch.

[gmaxwell]

The scheme in the paper doesn't really work. It turned out to be unimplementable as described and require additional keys (beyond the threshold) to reliably sign.  It also required multiple communication rounds, which is pretty burdensome on implementations (e.g. having to get your offline wallet out multiple times).