add mostly undocumented feature to disable/change the sensitivity of two-finger swipes.
`defaults com.codeux.irc.textual SwipeMinimumLength 0` will do the trick
as will `/defaults -d SwipeMinimumLength 0` in a future commit
add to /defaults a -f flag for double values. I was going to do -d but I wanted to avoid the confusion between -d and -del