So I'm practicing aa and hear talk of naughty aa tools. To learn good from bad, i'd like to see examples of aa done by skill vs automatically please.

i wanted to see aa done by auto but I'm thinking it's just something like blur tool.

There are 2 possible auto AA, in 24 bits color space or 8 bits color space.

AA info posted above demonstrates hand drawn AA vs 24 bits auto AntiAliasing (which is very color consuming and too easy to spot), but graphics editor specialized in the 8-bits field can AA your shapes using ONLY your established palette, thus seriously approaching but not beating a skilled hand drawn AA.

Back in the "pixel era" (meaning computer art from 80's to mid 90's)  where 8-bits graphics editors ruled the computer artscene, including both game art and demoscene art, Auto AA features probably emerged with programs like Brilliance (running on AmigaOS) using only two or three shades...

Rumor says that pixel artists still use these automatic functions to speed up AA procedures (as well as Brilliance, cosmigo's promotion graphic editor allows such tricks).

However these tricks are regarded today as taboo tools by Pixel Art communities that became very strict about pixel art definition in order to separate human achieved PA from machine achieved PA.

Thing that sounds to me a very complicated (impossible?) task mainly because skilled pixel fakers know how to scan, auto dither, auto AA a pic making you think that the gfx is entirely drawn by hand, more infos about the fake pixel art problem can be found here: Disintegration of the old graphics scene http://www.kameli.net/nocopy/disint.htm )

Thus leading to a neverending saga, started in the mid 90's called...

 "How to prove that your PA is genuine"

I don't really get this point, I'm quite interested in knowing these procedures. do you mean that pixel critics become less strict with commercial oriented projects?  

Can you provide extra explanations on this subject?

one thing is to make something as pixel art because technical restrictions demand graphics with a low amount of memory usage. in this aspect, your customer will be worried about the process and techniques you use.

another diferent thing is to make graphics that have a pixel art "look" because they want them to look like "old school graphics". in this case, your customer doesnt care what you did, as long as it looks cool.

and another diferent thing is to make pixel art with an artistic goal, wich in most cases fullfills diferent restrictions that you impose to yourself, and you use certain elements in order to achieve a result in order to either display your skills to others or for the pure joy of challenging yourself.

being able to discriminate between every piece's intention besides the amount of colors or the tools used on it is the diference between limiting pixel art as a graphic tool itself from a form of art. its true that is technique driven, but it can be more than that.