No, they do not suck. For example, "This technique helps you build a frobble faster." "No, you can build a frobble much faster if you have sentient nanobots!" "We don't have those. I am speaking of techniques that actually work in reality." "But implicit constraints suck for sharing knowledge!"

One of these two voices is saying something useful about how to do things better. To borrow a sports metaphor, it is moving the ball forward. That voice is not the voice that is complaining about the use of implicit constraints.