I too find the KM log file to be too verbose, 99% of the time. I think this is a problem when you are looking for log entries not related to these verbose entries. @peternlewis, I know you hate clutter, so how can you stand the clutter of the KM Log? 
IAC, there is nothing we as users can do about it, except to ignore it.
Many Mac developers offer an option for the level of their app's logging. Something like "Minimal, Normal, Verbose (debugging)". I don't care what you call it, but I would prefer minimal logging except when there is an error or unexpected behavior.
Well, maybe there is one thing we can do: write our own log processing tool so we don't have to look at the raw log. I have done this. See
MACRO: Display Last KM Macro Error
HTH.