Repeat after me: luminol is a presumptive test, luminol...
Brendan's faulty interrogation compromised his memory IMO. I take his subsequent statements, whether exculpatory or inculpatory, with generous grains of salt. For the sake of argument let us accept that there are bleach stains on his jeans. They cannot be dated by any means known to me. There are multiple explanations for such stains; they are not probative.
What I would like to know is what the pro-guilt commenters think caused the luminol-positive area to react, and why?