Hating testing

My son has standardized testing at his school this week. I hate standardized testing -- it's needlessly disruptive to his calm special-ed routine, and isn't going to tell us anything we don't already know. I'm sure the teachers hate it, too; in fact, while I was volunteering in the library today, a teacher walked by, stopped in the door and announced, apropos of nothing, "I hate standardized testing." I've gotten notes the past couple of days that my guy's behavior was lacking in the afternoon, and although there could be a number of reasons, I'm pretty quick to lay it on the testing he endured in the morning. Oh, hated testing! Is so much of it really so necessary? I'm all for accountability and everything, and keeping up standards, and making sure our students are learning things they need to know. But I've also seen sample pages of some of these tests, and I'm not sure I could pass them. I fear we've come to the point at which these tests have undergone so much editing-by-committee that they've lost any particular connection to a useful body of student knowledge. Couldn't we just go by grades, and hope for the best? Seems the only people who don't hate testing are the ones who keep foisting it upon us.