A Bitcoin improvement proposal, which could radically alter the Bitcoin network and its use
Discussion
It is a soft fork, so it can’t a really change anything about what bitcoin _can_ do; it can only enforce new restrictions or require 0 new restrictions, but it can’t violate restrictions already in place.
I don’t know if it’s a good idea or not, but they’re free to code it up and try it out with no effect on the network (of course they can’t put significant value into it as without a soft fork, these new signature-free transactions could be spent by anyone).