I've probably never had to say it aloud, and haven't come across that before, internally I've read 'et cetera d' for sure.

That said, 'etsy-dee' is somehow better to me than 'etsy', since it's like 'et C.D.' which makes some sort of sense.

(You could of course make the same argument for 'etsy', it's just that nobody reads 'etc.' as 'et see', it's always 'et cetera'.)