Sites are frequently designed to detect the presence of Flash, and degrade gracefully if it is absent. Flash blockers create usability problems for most users

Sites are frequently designed to detect the presence of Flash, and degrade gracefully if it is absent. Flash blockers create usability problems for most users by defeating those measures. Flash blockers are designed to create a placeholder for the Flash content. That is often defeated by Flash content that doesn't really correspond to any specific rectangle on the page. Together, these two situations mean that Flash blockers unceremoniously torpedo the principle of least surprise. Don't get me wrong, I love my Flash blocker. But it's a gadget for geeks, not a solution for the Web at large.