I know there are cases I don't know about, but personally I have yet to encounter a 700/800 system that allocates voice to the 700 MHz channels. They use those channels for data applications. To the best of my admittedly limted knowledge.
A proposed "guide to safe scanning" document would best be traded person to person or hosted at Dropbox, google drive, email, etc... there's no reason why this site would CHOOSE to host information that could be used to bend if not outright break certain laws. And we do understand that the legality of using a public safety radio to monitor a system is at the very least in the legal grey area.
In my case, I bought the software, I have the licenses required for the software and for all radio operations that apply to my radios as I use them, I'm a radio technician professionally, and I have a solid reputation with law enforcement in my area. I've definitely had a few dealings with the command level staff of my county's Sheriff's Department concerning my finding and returning lost/stolen/missing radios and I am certainly in good graces with them. They know that I'm a responsible citizen, very much on their side, and will proactively do the right thing with regard to encountering county property that got out improperly. A good reputation is EARNED. I've done the work and earned mine. I have literally been listening to local systems longer than most officers have been on the force. And NEVER had an issue. Well..there was one. But that was over a VHF radio and the officer in question was slapped down very authoritatively by the supervisor who obviously had a low opinion of that particular rookie cop. The rookie thought that it was not legal for a "mere civilian" to own a portable radio. Literally that was his thought. Despite my being able to cite the law verbatim. "I think they changed that law recently. I'm going to confiscate that radio if I'm right." Idiot.
Part of being a responsible listener is to use the information you hear as a guide to where to STAY AWAY FROM. I hear about a crash...I detour to avoid the traffic. Fire? I'm going the other way. Armed man/hostage situation? I'll leave that area alone. I won't ever be in a situation where my presence could add one more complicating factor to already stressed officers. Scanner people who use their radios to go find interesting things to watch are just the kind of MORONS that give the whole hobby a bad name.
Meanwhile I knew a guy (I can't really say he was a friend...) who programmed up his STX (this goes back a ways...) to listen to his county system, AND BE ABLE TO TRANSMIT...and he was showing it off to his "cop friends" (he was a full-on police groupie....) and one that wasn't his "friend" did the right thing and confiscated it and he avoided legal trouble by the skin of his teeth. ANOTHER IDIOT.