(no subject)
Bear with me. Suppose it's true that "critically, this apparatus of selfhood is at once (a) stable in its transcendence, (b) adaptive in its functional projections, and (c) creative/productive/expressive, enabling free self-creation."
Also assume monism and the law of non-contradiction as both a logical/metaphysical principle and a rationally regulatory one.
Consequently, the transcendent self is materially conditioned. The materiality will be conditioned by the functional projections. The self that is freely expressed will be the transcendental but ultimately material one, and the expression will also be material. The process of self-expression will be functional; the habit of the self-expressive function will be a project.
Rationality (non-contradiction) in existence demands that the functional projections preserve the subject's transcendental character by preserving it through expression over time and in spite of (or because of) context. Inauthentic projections--such as bad means "justified" by ends--are a kind of self-harm, as are inauthentic expressions, in non-trivial cases. So the price of irrationality is a kind of self-mutilation or suicide.
If a functional project, in a confrontation with reality, destabilizes its original transcendent origins, in worse case there is a break in identity. But more like there will be an evolution or sublation. We have discussed this process at length already--it is how we arrived at the current, purportedly stable theory of self.
How stable is it? Only as stable as the subject's transcendental character as it confronts its reality, which will (in practice, today) be complex and unpredictable and, for it, finite. Here, again, de Beauvoir's account is promising