It was just an example of what I'm doing for my particular situation where I don't have root access and I want some personal scripts for myself, I'm not saying you should choose the same location. If everyone is already sourcing the same file, I expect there's already a shared storage you are maintaining that everyone has access to.

About something breaking, I guess it's up to you and your team if you prefer functions, but it also means not everyone will need to be annoyed when someone else's code has a small syntax error. And also I expect the only errors you are able to get feedback about right now would be only structural syntax errors for the function declaration (I expect you don't have unit tests or anything like that for your bash functions..) so technically a function could still be broken and you wouldn't know until you use it.

Scripts also give the advantage of being able to use other languages beyond bash, if perl/python or others are available.

Anyway, you are free to have your reasons, I was just saying that root access is not necessarily needed.