Its quite an interesting example youve just given.
I was going to post something on this subject area, for a couple of reasons. First reason that a couple of weeks ago a certain ......., was asking what i had been doing, specifically in relation to my line of work.
I was in fact on a job 3 week Advanced Motorbike course, which im pleased to say i passed on Friday.
There are so many things i could bore you with, but i know that you would all find this topic quite interesting?
As a general rule, overtaking on a solid white line against, is
a no no, except when you fit the criteria in the highway code.
Even then, and i know your bmw overtake didnt fit into the criteria, if you start to put into the equation other factors like you say, (and in particular left hand bend) then you very much experienced the consequences.
With regard to left hand bends, although I would never say never, you have to look at the amount of unseen view, and how much this would increase as you move out to overtake.
We are very lucky on bike to have so much squirt, that you just know youll get by it very soon any way, so why risk a 9/10s overtake when around the corner will be a 10/10s view, so much more disciplined?
Compare the view, and in particular the early view, you can get on a right hand bend. This is where i would be looking to pass.
So in answer to your question i would advise against it, for what my sixpenneths worth.