Sorry but you're being completely illogical. If your reasoning was that 250.50 requires "all grounding electrodes described in 250.52(a)(1-7) that are present at a structure shall be bonded together forming the GES" regardless of 250.54 then you can't just decide willy-nilly that they only meant (1-3) and not (1-7). The only reason the code doesn't require (1-3) to be installed if none are present is that it would be outside of the scope of the electrical code to require a structure to have water service or a concrete or steel foundation. And it is incorrect that you *can't* install (1-3), only that they will not require any if those if the structure doesn't otherwise need them. (It's really an unnecessary distinction, but it's also actually inconsequential.) There is nothing about that distinction that allows you to logically infer that some can be auxiliary electrodes and others can't. If you don't think that following 250.54 (or 250.60) exempts an electrode from 250.50's 'bonded together' requirement, then the only thing that would let an electrode be exempt would be if it wasn't an electrode described in 250.52(A)(1-7).