https://m.youtube.com/watch?v=fst1IK_mrng&time_continue=2179
Skip the first 35 minutes, it's blank. Why they didn't edit out the dead time I have no idea.
Wuille's presentation on segwit is well worth watching.
Segwit is really an ingenious solution to inherent inefficiencies in Bitcoin, and has multiple benefits. Extra room in the blocks is just the icing on the cake.
fwiw same presentation at San Francisco bitcoin meetup:
https://youtu.be/NOYNZB5BCHM
that said SegWit is definitely ingenious, nevertheless a two critical points:
- proposed development timeframe is too short (look at issues reported by Peter Todd here http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-December/012103.html)
- in terms of block size increase it's equal to having a slow ramping to a new 1.3/1.5MB cap in 12-18months.