I don't know why theres a /warp toptower, but even if the warp is removed, you can /sethome at the top, and acro train there, still.
In an announcement, I read that it is illegal to suicide train, which is when you train acro, but kill yourself with a fall. It might have been okay to heal yourself afterwards. It wouldn't spam the player chat, however it would spam the console.
To wrap it all up, I'm not sure if you can do the second method (its only an idea), and that deleting the warp for toptower is useless, unless the flag is set up to disable home setting.