One of the most common issues that I run into in my work is getting all sort of questions which sound really strange. For example, I recently got a question that went something like this:

What is the impact of reflection on NHibernate’s performance?

I started to answer that there isn’t one that you would notice, even beyond the major optimizations that NH had in that role, you are accessing a remote database, which is much more expensive. But then they told me that they profiled the application and found some stuff there about that.

I asked them what their scenario was, and the exchange went like that:

Well, when we load a million rows…

And that is your problem…

To be fair, they actually had a reasonable reason to want to do that. I disagree with the solution that they had, but it was a reasonable approach to the problem at hand.