Basicly movement is mostly disabled during text chat message typing. Problem is when you want to capitalize a letter or use : or " or whatever symbol that requires SHIFT buttons, you can still move. Why this is a problem is because there are moments where you prefer to use written chat not VOIP. In this game meetings between random players are tense and if you want to use SHIFT for any reason while typing you sprint into them because you always face a newly met player. This is a problem because if you are trying to talk first, shoot later, you might have the tough luck to run into a player and get shot because he misinterprets it and thinks you might punch and KO him when your intention was to just type a ":D" (example). Movement should be 100% disabled during chats regardless what key you binded for sprinting or whatever (SHIFT is just the standard for almost all games).