Thank you, Guided!
I think you stated there exactly what the root problem is with these types of meditations.
You wrote: “However, as far as the 10-day introductory course is concerned, there’s not much stress put on this kind anapanasati and instead, one should, I quote, “work with the body, not the mind,” therefore one should disregard ALL thoughts during the meditation itself and focus only on vedana, according to all the assistant teachers I met.”
It is the mind that needs to be purified.
– Our physical body will die within about 100 years.
– However, the “contents of the mind” will be carried to the next life, with its gati, asava, anusaya,, etc.
Buddha taught that one should stop ONLY those thoughts that are defiled (immoral or sensual in nature). Those are akusala sankappa and kama sankappa.
– One needs to CULTIVATE moral and non-sensual thoughts. Those are kusala and nekkhamma sankappa.
– Here, “non-sensual” means thoughts that do not involve satisfying especially the taste, smell, and touch. Any thoughts about vision and sounds that are relevant to satisfying taste, smell, and touch need to be avoided too. Some examples are thoughts about food, sex, nice fragrances.
In order to set the background, one first needs to realize the unfruitfulness and dangers in engaging in activities/speech/thoughts about sensory pleasures. That is to learn and comprehend Tilakkhana or the anicca, dukkha, anatta nature of this world.
June 13, 2020: I had posted the English translation of a long discourse by Waharaka Thero here. I just removed it since it needs some revision. I will post the revised version when ready.