Hi again Kelly, a quick follow up. I did notice that the "size" parameter referenced for GEN02 at csounds.com is not the same as at csound.com, it would appear to perhaps be outdated or something. From csounds.com:
size -- number of points in the table. Must be a power of 2 or a power-of-2 plus 1 (see f statement). The maximum tablesize is 16777216 (224) points.

No reference to using a size of 0.

I'm also at a loss to explain that both sites seem to suggest a negative gen routine number (-2) is required or values will be normalized. The manual reads:
If p4 (the GEN routine number) is positive, the table will be post-normalized (rescaled to a maximum absolute value of 1 after generation). A negative p4 will cause rescaling to be skipped. You will usually want to use -2 with this GEN function, so that your values are not normalized.

However my ears are not so bad that this would have gone undetected. I think... ;) Nonetheless, adding a print command to the instrument confirms that a negative gen number is not required, the notes reported are clearly not normalized to a max value of 1. I've used this gen routine for several of my pieces and it never seemed to require a neg. gen routine number. Perhaps the 0 size causes some initialization to be skipped? I have no idea. 

Perhaps a ticket should be filed on github or maybe someone here can offer clarification. 

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