I think one danger with using a phone whether it is for business or just so your kids can get a hold of you is you can very easily get helpful information that you weren't intending to get.
Here is an example:
Ring, Ring
Angler: Hello
Client: Hi Marcus it's John from accounting, hey are you by your computer right now, I need you to verify something for me.
Angler: Sorry John, but I'm actually in a bass tournament on lake St. Clair right now, I'll be done in a few hours.
Client: Aw man I'm jealous, I fished with a buddy out there last week. We caught a ton on the south shore just before that storm hit the lake. I can't wait to get out again.
Angler: Maybe we'll get out some time, I'll call you later today, see ya!
Client: by
This may seem like a joke to some of you but I know in my experiences that often times when people call me on my cell phone, and I tell them I'm fishing, they immediately tell you about the last time they fished. I do the same thing with my fishing buddies when I call them. Perhaps this is something that is considered when making a rule such as this. The fact that there is money involved makes it necessary to take great measures to ensure that all participants are competing fairly. I still have not given this subject enough thought to know how I would write this rule best, I just thought I would present a situation that some of you might not have thought of.
Marcus