If we were to implement tips, which is a great idea, then it should be both triggered tips and things while loading the map, and things that pop up when you enter a server. I suggest all people that join the server start in Observer though, so they are not reading tips when they spawn and die. Also, many times I have to explain to new people how to join a team when they are observer, so when you are observer, there should be an ongoing message saying "Hit Escape to get the in game menu, and select Join Team to play!" or something to that effect.
-Cusoman