Overlapping POI's from multiple tourguides

I'm pretty new to the GPI world so this may be a simple question. I apologize in advance if this is common knowledge. I have a concern when creating tourguides that they will have too many overlapping POI's to be useful. How do I know my tourguides will not overlap with other people's tourguides.

Just as an example, let's say a tourguide for a downtown area covers "places to eat" but another tourguide covers "places to shop" in the same downtown area. They both use an JPG / MP3 for image / audio (and let's assume the audio is long enough to require a few seconds - like perhaps 30 seconds).

If both tourguides are loaded on a Nuvi as gpi files, when the Nuvi gets downtown, won't it be going off all the time? The POI's would probably be so close that the proximity setting would cause things to overlap. My understanding is that the first POI encountered plays it's MP3 and that the rest get queued up behind it.

Wouldn't it be a problem that in a few minutes of walking or driving in a concentrated downtown area the Nuvi would load up a whole bunch of audio that could take many minutes to roll through?

What happens when there are thousands of gpi tourguides for all these downtown areas? Won't they all step all over each other? Or is the solution to only load one? But if that is the case, how inconvenient will it be to have to reload GPI's when it's time to "eat" vs. time to "shop"?

Or, what if two (or more) tours want to feature the same POI at the same location - such as the Lincoln Memorial? Is there any way to enable only one tourguide even though a bunch of tourguides are loaded in case you want to switch to an alternate?

I realize the "places to eat" and "places to shop" may not be the best examples of tourguide material, but hopefully you get my drift of overlapping tourguide POIs from multiple tourguides.

Thanks.