I think that Richardson for one year is not a good trade. If you look at it from the perspective that we are only swapping a 2 and 3, and giving up Kearse, then I think the argument may be made it is a good deal even if he is out after one year. However, that overlooks other deals we may have been able to secure (granted if any) and perhaps we may have been able to land something better than a one year rental with some other team.
I think Richardson could play a major role in us winning another championship, but I do not think it is this year. I honestly cannot see us winning the SB with the current OL and I think our defense is good but aging. I am hoping Richardson acts as a catalyst to rejuvenate the defense and am still hoping he is the piece that puts us back in 2013 form (as I think the pass rush has been our biggest problem the past 2 years outside of OL of course). I understand we only gave up a TD or less in preseason, but half of preseason was against offensive players who did not make the cut of their team either. Plus our opening series on defense were not exactly impressive by any stretch.
One the other side of the coin, this trade also gives us a year to court him for a longer deal so maybe it is a good trade from that perspective.