[curves] Threshold ECDSA / comparison to Schnorr

[Trevor Perrin]

Some advances have been made on practical threshold ECDSA by Steven
Goldfeder et al:

https://freedom-to-tinker.com/blog/stevenag/threshold-signatures-for-bitcoin-wallets-are-finally-here/
http://www.cs.princeton.edu/~stevenag/threshold_sigs.pdf

Is anyone able to breakdown how this compares to threshold Schnorr?
http://cacr.uwaterloo.ca/techreports/2001/corr2001-13.ps

In particular:  Does Schnorr still hold an advantage in this area, or
has ECDSA closed the gap?  What are the differences with respect to:
 - trust assumptions (trusted setup, robustness to misbehaving parties)
 - communication costs (in particular, # of rounds)
 - computation costs
 - implementation complexity


Trevor