This bypass allows you to load your own lua files (hacks) ingame without any hassle.
By default the sv_allowcslua is set to 0 and that is their way of telling your client to not load anything besides what the server wants you to, kind of.
So if you press bypass on this it sets the variable to 1 and allows you to load files.
Like aimbots and such. (Anything that is made in lua)
That answer your question?