Simon, I don't mean to start any type of bad feelings as I do not mean any disrespect as your expertise here is invaluable to the site, I learned alot on satellite stuff reading your posts. On this issue though I think we just agree to disagree.
All I am saying is that there are ground lines on gas lines and that is what I am talking about, NOT THE ACTUAL GAS PIPE. It is almost the exact same setup as the water line ground that homes have and I know for a fact in MI that many older homes have a Gas and water line ground system. If you are a certified firefighter in west and norhern lower michigan, than please put me in my place, but if you do not know the envirionment of the area and the different setups of homes in this area, please don't try to tell me I don't know my own house or my parents own house.
When you get a house inspected around here and it is old enough to have an old gas ground, you have two options. You can leave it live, but must bond it to the water system or you can disconnect it at the owners expense.
I will grant you this the new NEC code states that newer homes and rewires must bond any metal pipe in a home that could become energized, this is different now then the old dual ground system. So now all gas pipes, water pipes etc must be bonded as they all have the potential to be energized. Simple applicane grounding on Furnaces and stoves and other units that attach to both services may or may not have the Equipment Grounding Conductor in them to bond the systems and the home must have a bond between the two systems at least once.
Again, however in older homes that have not had any work done, the older dual ground systems still exist.
http://www.nciaei.org/bonding_revisited.htm
EDIT:
here is an cut and paste from my local building codes department after I sent them and email on the bonding in my house on this issue.
7.1 Gas Piping Bonding and Grounding
Each portion of a gas piping system upstream from the equipment shutoff valve shall be electrically continuous and bonded to any grounding electrode, as defined by the National Electrical Code. ANSI/NFPA 70.
they go on to explain that the bonding in my house is code for many older homes and that all gas lines must be grounded to a water line ground or their own system, my house has both systems, but I just checked with my coworker and his home is bonded to his water line.
Ok, edit again as they emailed me this in follow up to my reply to message aboe, but I am not sure why as I was just saying thanks
7.3 Electrical Circuits
Electrical circuits shall not utilize gas piping or components as conductors.
Exception: Low-voltage (50 volts or less) control circuits, ignition circuits, and electric flame detection device circuits shall be permitted to make use of piping or components for a part of an electrical circuit.
So apparently, gas lines can carry much more voltage than I thought, which I guess explains a little more how the broadband over gaslines would work.
End Edit
What about broadband over gas lines? This will require a bit of electricity to carry the signal.
http://www.nethercomm.com/headline2.htm
Here is an article on the same thing
http://www.businessweek.com/the_thread/techbeat/archives/2005/05/whats_cooking_b.html?campaign_id=rss_blog_techbeat
So, I would take all this to mean that a water ground is your best choice, but in this area, your gas lines are grounded and that ground can be used to ground other things and since the advent of the the new NEC code, the gas lines and older gasline grounding systems are bonded to the water system, so in essence, you are bonding to the water ground.
On the switch grounding issues. I don't disagree that they can be used as ground blocks, I use mine that way, but I have a problem with what you are saying as my manual does not allude to what you say.
Here is a link to DPP44 manual
http://www.montanasatellite.com/manuals/DP_Plus_44_Switch_Installation_Manual.pdf
Page 8 doesn't state what you said. This is same manual I have.
Also here is the DP34 manual
http://www.satelliteone.com/dish/support/DISH_Pro_DP34_Installation_Guide.pdf
Page 7 states it can be used as a ground block, but notice page 10, there is a little disclaimer stating to obey NEC and local codes.
The DPP44 manual I have and the one online are missing the line that is on page 7 of the DP34 manual.
I cannot post a link to my local code as they do not have it online, only repeals and amendments.
However, can you post a scan of your manual? I am now curious as it seems we have completely different manuals.