G has been automated since I-don't-remember-when and it takes a lot of testing to get something, many webmasters here (including me) believe: follow your guts and common sense, because G sometimes advice questionable stuff.

Never forget that Google is only interested in things that scale across a large number of (whatever - advertisers, users, publishers) so of course it's automated. Everything with Google is data driven - and it's their data, not necessarily ours.

Every site is different. I've been running experiments for years and have a pretty good idea what works for my site but I still run experiments.

I've been to a a few Google AdSense events on the west & east coasts and find it disturbing that the average AdSense employee indicates that most of them were in grade school and high school when the AdSense program was introduced. In speaking with them it is my impression that the same Googlers advising publishers do not have extensive real-world publishing experience themselves.

I find it difficult to trust advice from people who have little to no actual experience. I have never trusted academically arrived knowledge because it is not based experience and is prone to mistaken assumptions and blind spots.

most of them were in grade school

That was my impression, too. Although as I get older, more and more people look like they just got out of grade school. I do think most of the people that Google hires to work with Adsense are just out of college. Smart people, but as you say, very wet behind the ears.

What I meant to say was that I assume if I if it says on performance reports lets say 100 clicks at .30 a piece so I'll get $30 right?
Well from that article it sounds like the amount of clicks that they are saying you got, is not necessarily true. Sort of like they decide beforehand how much you should get and then adjust the amount of clicks and cpc accordingly.
Is that how it sounds like to you?

Sort of like they decide beforehand how much you should get and then adjust the amount of clicks and cpc accordingly.

No. If it says that you've gotten 100 clicks at 30 cents, then for the moment, that's what you've got. It can change, though, and often does, because Google is constantly adjusting for invalid clicks, which can happen for all sorts of reasons. If I log in and out of my account a lot within a short period of time, I'll see the revenue total go up, but also come down.

How does that explain this?

"First, be aware that our systems take time to adjust to your changes; it may be several days before the full effects of a recommendation implementation, positive or negative, can be seen."

Clicks being deleted today may have been clicks you got several days ago. Bottom line is, if you do Adsense, Google is the boss. They giveth and they taketh away. You really can't argue with them and expect to win. All you can do to reduce deductions is improve your traffic quality and make sure that your site is designed so clicks happen honestly.

I do think most of the people that Google hires to work with Adsense are just out of college

Can't speak to AdSense, but here in Ann Arbor (where the AdWords HQ is located) Google actually teaches AdWords classes in the public high schools - Google's trying to get them BEFORE they get to college. Maybe AdSense too.

"First, be aware that our systems take time to adjust to your changes; it may be several days before the full effects of a recommendation implementation, positive or negative, can be seen."

I see this has having to do not with invalid clickitude (yea I just made that word up) but how soon it takes their recommendations to pay off. I've had some recommendations pay off instantly (switch to a different ad size in a different placement) and others that took a few days to a few weeks to show an improvement. Heck, it took Google a slap year to get the targeting right for my sites back when everything was 100% contextual. And the data is constantly changing, too.

So asking if AdSense is "accurate" doesn't make much sense to me. If you're asking if they're playing square with us as regards earnings - well, nobody but Google knows, and I prefer to think they are. If you are asking whether or not their recommendations are worth pursuing, only you can decide that. I always listen when Google suggests something, but I don't always implement. I have to trust my own instincts.

The simulation may show that an image ad on your text-only placement would make more, but it can't definitely know that your visitors would click on it.