The Satipatthanasamyutta of the Samyutta Nikaya (47.*) offers... a less agglutinative approach to satipatthana, which I feel allows for a very detailed approach. For example, SN 47.40 distinguishes the establishment of mindfulness (which includes the red text you've referenced) from the development of mindfulness; this last is "satipatthanabhavana", and involves "contemplating the nature of origination...", "...vanishing...", and "...origination & vanishing..." in the four categories.mikenz66 wrote:Seems the same as the Satipatthana Sutta, but without the detailed explanation of the various mental qualities (dhammas).
Here, and in the quote you provide, watching closely with equanimity is to see with discernment the abandoning of greed & distress (BB: covetousness & displeasure). This use of equanimity is brought up again at SN 54.10, in the Anapanasatisamyutta. This is a clear instruction, and numerous subtleties such as these are explicated throughout the many Suttas in these sections of the Samyutta.
Given the potential expansiveness of these topics, I want to stay closely focused within the domain of the OP, to wit: there is no "two truths" description given anywhere throughout these sections, even though the Buddha is careful to make distinctions such as satipatthana/satipatthanabhavana, or anapanasati/anapanasatisamadhi. At no point does a "two truths" description seem to clarify any aspect of these practices, and therefore I think the interpolation is unwarranted and unhelpful, perhaps even obfuscatory.
What does holding a two truths notion actually help you to understand?