The sort of energy cultivation you refer to is within the parameters of information Master Lin has shared more personally in seminars/retreats. I wouldn't say it is part of the core practice of what SFQ is. More in the category of additional 'methods' one can engage with if so inclined.
I would offer one related suggestion relative to your alignments in SFQ exercise, that you not pull up the huiyin area while you practice SFQ, if that is the case. Master Lin mentioned that it isn't necessary, and 'can' cause constipation. I am not saying don't ever do it, relative to some other cultivation practice method, and that you will get constipated if you do it. More so, that SFQ has it own unique alignments and results of those alignments. I find that pulling up the huiyin in a SFQ alignment, is a sort of tension and more physical orientation, that doesn't have to be there. Reverse breathing can be done with or without physically pulling up the bottom.
Systems and methods, have different focus's and intentions in them. That said, I would say you are talking a method, versus a system or path that works with more aspects of self and as well as helping others(a facet of compassion). Yin and yang aspects/qualities, relations to martial, medical and spiritual, and how wisdom and compassion present themselves or shape the results, are all in play.
Mantak Chia's information is valid. Practices shape you. If you focused on Mantak Chia's information, or on SFQ, completely, the end result would be very different in many ways, even though similar elements are in play. I think it is good to have some sense of why we do the practices we do. Not just to do them because there is a strong result. If you do a practice that imparts a type of power or ability, how will the power be then channelled, or put to use. Is it just about me, or something else...