Thank you, again, Tom Andrews, for continuing to answer my questions long after your passing. 
I've been struggling with what to hold constant with all the possibilities for experimentation. Today, re-reading an essay after Codeine Diary, I found this:
"...so much is open-ended when you write a memoir--I'm thinking of the 'writerly' decisions you make: about tone, pacing, structure, diction, repetition, what's left unspoken, and so on. The facts you're writing about, however, are 'closed,' even though there is plenty of room to approach them from different angles, or to acknowledge that you remember them differently at different times, within the memoir. But, in the end, the facts ...are the only 'closed' element amid all the open-ended ones."