1) Taking everything that actually happened in the past two years, and saying, "Well that was a bad trade."
2) Taking everything we knew at the time, and saying whether it was a bad trade.
It's more fair to the parties involved to use the 2nd method, but it's probably more realistic to use the first. The second goes into whether or not it was a "bad" trade, the first essentially tells us whether or not it worked out.
So knowing what I know now, would I trade a recovering addict(relapse percentage between 50%-90%) who also was a health concern, who had had one good year, but had the potential to be an MVP for a 25 year old pitcher who also had great potential, but had his head in the clouds and had never put together all the pieces?
Every day of the week.
Would I trade two MVP caliber seasons(out of 3) for one spectacular year, one so-so year, and one injury shortened year with potential? Probably not.
I think if we're to judge trades, we should judge based on the mind set involved and not necessarily the results. That trade may have been the right trade, even if it worked out poorly. Other trades may be wrong trades, even if they work out well. We pay the GM's and scouts to be good evaluators, not fortune tellers.
That said. The trade's done. It's over. Edison Volquez is no more nor less of a pitcher because he was traded for Josh Hamilton. Josh Hamilton is no more or less of a ballplayer because he was a number one draft pick who nearly wrecked his life before being signed as a rule 5 pick.