To be clear, Kip is talking about a different field than the flight park or I would have mentioned that it is not a place to mix kites and gliders. The gliders will be pissed if they see a kite while they are even thinking about flying...and rightfully so. I flew my paraglider at Skyline with kites once and it was so hard to know where the kites were going to be. They move too fast to account for them while you are flying.
Kip, correct me if I am wrong, but you were riding the big flat field South/West of the frontage road adjacent to the freeway (below the groups of sledders that ride downhill from the frontage road). That field is not part of the flight park, (where Peter was) but still has a huge venturi effect (i.e. the potential to feel great setting up a 17M and then suddenly find yourself wishing you had a 7M) and there is no safety net from the freeway. That would be bad.
I believe Herriman or Lehi both have tons of similar fields that can be poached in similar conditions without the danger.
Seek forth and go ride a golf course.