While I'll agree with most of what you say, I'm not sure I'd quite go this far. Obviously, this is going to depend on what people really need. The average person out there probably really doesn't need a 2.8 lens, especially in a longer lens where those get pretty pricey and heavy. And for many people, the IS is indeed fairly useful. Know what you're going to shoot, and make your decisions based on that. For me, I'm a big fan of the canon 70-300 IS. Yeah, it's a little slower, but it's still an awfully nice lens for a non-L lens. And for me, for what I tend to shoot, I'd rather have the longer slower lens (plus $700) than the 2.8L 70-200 lens. But then, I don't have the budget for the 1D either . I won't lie and say I never had circumstances when I wish I had a faster lens though, although most of the time when I do I'd be ok with a shorter lens.

Most of my R/C plane shooting has been done with that 70-300 is. In general these conditions tend to be under fairly bright, sunny days. I've never felt the lack of a faster lens has been a big issue for this. I've even managed to take a few bird photos in the last year and a half that I'm truly proud of. Of course, most of those haven't been flying, which is just as well, I'm lousy at tracking birds in flight .

But anyways, I'm not saying it was bad advice, I'm just saying that one should think about one's needs before spending the money on something that may be overkill for them.