Discussions with a clear Si dom go thusly:
*I tell story I posted here*
"Sure I have strong memories, but that doesn't seem useful, so if that is Si, Si is useless"
Same Si dom reports telling favorite stories from own life experiences over and over again (reliving memories much in the same way I describe here), noticing small disturbances in detail from across the room, fixation with order or cleaniless to "maintain sanity," talks about rules and fair division of labor, preventative measures to maintain health, and has a surprisingly subtle critiquing system for aesthetic value.
Based on this and what I've observed from other Si doms or aux I would never think that I was manifesting Si dominance or auxillary in this manner. Just wanted to note that.