Honestly, that was the exact kind of trade I keep hearing people call for. Trout was in the midst of a great rookie season, these guys were high-risk, high-potential prospects (neither of the pitchers panned out, btw), and people were calling for Dipoto to make a move to shore up the staff for a potential wild-card run. Which failed, as they couldn't overtake the Rangers and Orioles. This was never going to be a 'long term' sign for the Angels - it was always a rental to 'get them over the hump'.
Those who don't learn from past mistakes are doomed to repeat them.