Hills, times and perceptions

I ran two 5K's just two weeks apart and my times were 32:46 and 33:44.  I figured it made sense, they're both at the faster end of what I've been running lately, and the second race was hillier (Boston vs the "Worcester Foothills".  So, I did what any good engineer would do and pop on over to RunKeeper to see what the difference in Feet Climbed was.  I was a bit surprised.

First race: BAA 5K.  It runs along Comm Ave, and the "biggest" hill is going under Mass Ave. for an almost 30 ft hill.  And yet, the feet climbed totaled 280 ft.  Here's my RunKeeper File.

Then, two weeks later, I ran the AMSA Inaugural 5K. I swear to you, this race felt like it was uphill, both ways.  In actuality, there was a short up hill, a long downhill, then rolling hills then reverse of the first two hills.  That was a 120 ft climb in about 1/3 of a mile, including one stretch that I need to put my Prius into "super break" mode to not roll backwards down the hill.  But, the overall climb was only 228 ft! That would be LESS hilly than the BAA 5K. Here, check out RunKeeper.

A minutes slower, but 60 feet less of hills? Different day, so it's within my normal error of pace?  Technical glitch? (I've seen most running app's get confused about elevation near water. Every time I cross the Charles, my elevation goes to 0 ft, even though I'm not walking on water!).