@able2ask,
First of all, just to be clear, if what I wrote before led you to believe that I'm criticizing Mahayana in favor of Theravada, then I didn't express myself thoroughly. Both sport major doctrinal and pedagogical divergences from what the Buddha of the Sutta Pitaka taught, based on my direct observations of both lay and ordained people in both schools.
Anyway, your questions are good and legitimate. I think the first can be resolved by understanding what is called the Buddha's "skill in means," which you alluded to with the phrase "provisional teachings." In order to teach to those steeped in the Vedas, Vedic language and imagery is the most appropriate means to provide the best stepping stone to greater understanding. (You seem well enough informed that I probably don't need to explain that in more detail.) The
dhamma being a raft for crossing, but to be laid down after the crossing is done, etc.
The Mahayana position you mention could be explained in much the same way. An advanced practitioner could comprehend
sunyatta in a way that a beginner or intermediate could not. In any event, I didn't say that ALL Mahayana doctrines contradict the Pali Canon, and
sunyatta is not one of the Mahayana doctrines that I mentioned as doing so. "True Self" is the one I mentioned, and I could have included the soteriological aspects of the Pure Land sect's doctrines. If you examine the Pali teachings closely, you'll see that they are anything BUT soteriological, I think.
Regardless of what the
Prajñāpāramitā Sūtra says, (Mahayana) Buddhists here in Korea and elsewhere are taught a version of the dhamma that leads them to believe that they personally will experience an afterlife. If there are monks who understand it differently, they don't teach it to the lay people. Perhaps this is also skills in means, but both Theravadin and Mahayana lay people are led - even encouraged - to believe in afterlives that they will personally experience, despite the Buddha's exposition on
anatta.
When I was a novice monk in Thailand, one of the English-speaking Thai monks who had been very friendly to me was explaining a dhamma talk given the evening before by the abbot (ajahn) to a group of laypeople visiting our monastery. Part of it had to do with securing a favorable rebirth. So I asked that monk what was reborn, considering the doctrine of
anatta. He couldn't answer, except to say, "I'm sure the ajahn knows." After that, he wasn't so friendly to me anymore. I felt sorry about that, and thought I should've just kept my mouth shut about it.
Both Theravadin and Mahayana laypeople, and some monks, at least the ones I've talked to, profess a belief in a version of rebirth that is for all practical purposes indistinguishable from reincarnation. No one that I've talked to, lay or ordained, spends much - if any - time trying to understand
anatta or even give it the role in the training that the Buddha of the Pali Canon alloted for it.