Sounds like he's saying that using keywords for their intended purpose is a plus, abusing them will bite you. And that is as it should be. A six hundred word page probably shouldn't have any more than 4-500 keywords, eh?
I've always treated meta keywords as a sort of short-form summary in which to emphasize the handful of terms that best describe the pages' reason for existence.
And that could be why I'm happy to see a few thousand hits a month while other sites get that many a minute. But I'll take my properly-directed traffic and be happy with it ... I'm just tickled that anyone reads my gibberish at all.
If someone also wants to click on an ad once in a while, that's fine, too. I only costs me about $100 a year to keep the site active so it's not like I need a huge conversion percentage for the site to liquidate its own expenses.