You're right that caching is the easiest thing. That's why people do it. The problem is that they do it right away, and then eventually the things slows down

You're right that caching is the easiest thing. That's why people do it. The problem is that they do it right away, and then eventually the things slows down anyway, and then they're hosed. In the example you describe, the hosing would be relatively minor, since you could hand-optimize the queries and simply plug them back in. In the more common case of caching your 50-query homepage, you might end up needing to buy more servers without ever realizing that you could have gotten it down to one query. So yeah, if you're confident that your signup page is never going to get the sort of load that'll slow it down despite your caching then you're right, you're all set.