The Jeff Galloway programs emphasize a run/walk method too. I used his program to get ready for this year's race.
In a nutshell, his program starts with building yourself up to walking 30 mins. without being winded, then adding in short jogging intervals until you work yourself up to adding walking breaks into your jog. Does that make any sense?
I know this is going to come as a complete surprise to everyone...but I'm a highly competitive person.
Last year when I was training for my 5K and 10K and saw it more as weakness to walk in my runs, but since I was giving a much longer race a try this year I decided to try the run/walk method. I was amazed at how well it works and how my time really didn't suffer as a result of the walking breaks. One last tidbit from the Cliff Bar Pace Team, they say that if you can work yourself up to jogging 5 miles...they say you can easily complete a Half Marathon using the run/walk method.
Now, a 16 min. mile isn't a stroll in the park, but it isn't a terribly brisk pace either. If anyone is curious to see what their natural pace is, I would suggest going down to your local high school and walking their track to get an idea of where you stand.