Hi Bochen,
Thankfully, I think the lack of a ban section here indicates just how infrequent BW bans occur. If you have a routine that's well away from player traffic, it can help.
In over a year of botting with multiple accounts, I've only received one ban, and that was likely due to running into a wall or something, being reported, and having a GM catch it. Of course, the longer you let it run (providing it doesn't time out or crash, which can happen for any number of reasons, including nav server overload), the greater the chance that something will occur which gets you reported, so pick your spots well. Also, in my opinion, it's safest to create your own grind profiles and avoid the public ones.
Good luck,
-D