tsearch2 avoiding firing of triggers.....

For some reason, I feel as though I have asked this before but I can't
find it anywhere..... I hope it is not repetitive!

I have various triggers and rules in my database, mostly for keeping
tsearch2 updated and (now) materialized views. I'd say probably 90% of
the updates to my database do not require these triggers/rules to fire
off, for example the materialized view trigger only needs to execute when
the category a record is in changes. The tsearch2 stuff, only when the
relevant data fields have changed.

Is there some way to either explicitly prevent the trigger/rules from
firing, or modify them in some way so that they only update when necessary?

Thanks!

- Greg