I think you're arguing that without good compiler authors, a typical application developer would be inherently unproductive. Which is true — compilers are necessary tools, and it's necessary that they be good.

But what I was suggesting is that one does not need to be capable of being both a compiler author and an application developer (if, for the sake of discussion, we avoid any semantic arguments and treat these as generally different things) to be of good value. I don't know how to, say, write a proper lexer, or write any assembly worth any salt at all, but I can write what I consider to be good, reliable application code at a reasonable level of productivity.

>People don't tolerate compiler bugs very well. I'd say there's quite a bit of overlap.

I don't see how your first point is related to the second. The goal for most webapps is to get something that works most of the time. Most software engineers simply don't need to worry about their third nine, much less their fourth