I haven't been inclined to assist because chanlimit.tcl wasn't designed for extremely low margins in terms of both the interval and limit setting. I consider it a bit of an abuse of the feature -- too many channels these days are pointlessly flooded with +l changes.
If the reason for setting such a frequent interval is problems with low limits being set after netsplits, you might want to try increasing the wait-split setting in your bot's config file. Unless the behaviour of [chanlist] has recently changed, the bot will still count split users as if they were on the channel, and only splits that last longer than wait-split will cause a problem.
well, actually no.
its not because of net-splits. but the channel the bot is in may have more than 6 join in 1 minute (and i have the limit set to +6), so I don't want the channel to get full, that's why I want the bot to check for limits every 30seconds.