Good cautions, dvduval. I do think that as long as query profiles is in the mix - and it definitely is BIGTIME - then they will catch and tweak any user dissatisfaction before it generates long-term effects.
I noticed a long while back that certain query terms would simply not show transactional sites on page one, no matter how strong the page or domain, and no matter how much it seemed like the right audience for the content. Certainly Adwords purchased for that search were getting clicks and conversions.
After using up a good amount of resources trying to rank "money pages" for queries that Google had profiled as informational, I got the message. It became clear that the taxonomy mis-match of query intention against webpage classification would undermine every other aspect of the ranking algo - title tags, anchor text, backlink power etc.