If I can find the reference I will pass it along but he clearly stated that exposure is the preferred and perhaps proper way to do it…maybe because the adjustment happens early in the pipeline and changes in filmic are later??? I don’t recall the logic…I don’t think exposure has any effect on rw and rb but I think they might change if you move the middle gray…this might be the desired result wrt dynamic range adjust wrt middle gray but maybe not?? In any case if you get the results you want I would use the method that suits you best…and as Chris said…not sure if it comes preset but you can hold down the e key and use the scroll wheel at any time for exposure changes even when you are in filmic or some other module