Just pulled my splits (taken blindly by pushing the button while the face was taped over) from my half marathon today. This is just where the splits fell - without looking at the watch at all, and trying to keep it subjectively EASY for the first five miles, MODERATE for the second 5 miles, and HARD for the last 5K:
1 10:24
2 10:18
3 10:46
4 10:51
5 10:58
6 10:51
7 11:31 (hilly turnaround)
8 11:37 (hilly turnaround)
9 11:04
10 11:02
11 11:19
12 11:17
13 11:38
0.1 1:07
Average: 11:02 min/mile
Two somewhat faster first miles, one slow final tired mile, two slow miles at the very hilly turnaround with two passes past the water stop, and eight other miles all within 33 seconds of each other. Of course, that's all along the very flat, straight rail-trail, so it shouldn't be so surprising they're fairly consistent.