I was approximating when I said "April/May" to keep the comment concise.  I believe it was actually part way into June that the red hot start ended, when they reached 20 games over .500.  They finished the season 12 games over .500, meaning they were a below-.500 team for the rest of the season after that point (the majority of the season).

You're right that the whole season still counts, of course.  However, when projecting how good a team going forward (like into the playoffs, or into next season), it's prudent to assess the trends.  In 2007, for instance, they were also just an average-ish team, but they went on a hot streak at the right time (entering the playoffs). I think this year they were just an average team (a bit below, actually, given that .500 is average) that had an anomalous hot streak at the start of the season. If this same team were fielded next year, I'd project an over/under of about 78 wins.