Since comments have been disabled once again (seriously, comments should be enabled by default!), a topic to discuss the article.
My main issue with it: why do people insist on categorizing Hidden Power as a Normal-type attack? Hidden Power is a “random” (not really, it actually depends on IV) type fast-move. The only “Normal-Type” effect it has, is that it will get its weatherboost from partly-clouded, and not from its effective type. So Hidden Power - Ice will get weather boosted during the more common partly clouded weather, instead of the rare snowy weather or fog, for example.
So, my ideal Porygon-Z would probably be Hidden Power (Grass) with Solar Beam or something like that. No STAB, but would make it a nice Grass Type with few weaknesses.