IMHO the LPS ground system _must_ be bonded to all other grounding electrodes, otherwise earth 'step potentials' could be coupled via the _separate_ grounding electrodes to cause differences of potential on different metal components which are separately grounded.

With that said, it would seem to me that the bonding and lightning down conductors should be routed so that current is not likely to be coupled into the building electrical system via these bonds.

When you consider lightning strikes, a direct hit is much less likely than a nearby hit which causes ground currents. You must design for these earth currents, not just the direct hit.

-Jon