There are certain maps that change gravity, death star escape for example, that have not reset gravity when changing to the next map. This is a primary use of the gravity command. We tell you not you use it not only because there is a chance it will mess up the server, but because there is no real reason to use it. The Terms Of Service states that all admin commands must be used sparingly and appropriately. Aside from the example given there should not be any appropriate reason to change the gravity and if there is a reason, it should only be used to Reset the gravity to its original number.
Also why should we remove commands that are not supposed to be used or abused. The rcon commands are faster and meant to be used when needed to reset the entire server(really the only time you should be using it). The reasoning behind certain commands being removed is there is no need to teleport or revive people at all. Ever. Gravity needs to be fixed once in a blue moon and rcon_setgravity 800 or whatever it is solves that problem.
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