The more interesting point would be like in the example provided in the article (billing half an hour for mailing) where the system considers the charge for the stated work to be excessive but the client may not be in as strong a position to question it as with the clear cut example you gave.
Definitely interesting times though!
We (SimpleLegal) will work with those guidelines and train our models accordingly.
Example: Walmart's Outside Counsel billing guidelines http://www.acc.com/advocacy/valuechallenge/toolkit/loader.cf...
As bradleyjg points out, some charges make their way onto a bill when they shouldn't. It's usually not malicious.
The problem is that legal bills don't get enough attention from the law firm. They rely on the client to tell them when something is a problem. We make that process easier. And hopefully everybody, even the law firm, is happier.
Beyond that larger clients are negotiating (imposing really) explicit conditions into thier agreements to prevent abusive billing. Things like minimum detail requirements (no more "5hr - lgl resrh"), no first year associates, no clerical work, etc. Then there's capped and flat fee billing.
Definitely a time of big changes.