“How do you determine the validity and quality of anonymous pal reviews, that you never have an opportunity to see?”
I don’t, the editor does.
“Extended peer review is open for all to see.”
Open for all to see but with only a few qualified to judge.
“Make it open” sounds nice and everything, I mean who isn’t against things being open? The argument is really not between “open” versus “not open” but rather between “selection” and “no selection”. In the no selection scenario all voices are equal, regardless of quality and accuracy. In the selection scenario someone has to do the selecting.
Pointing out flaws in the current selection process is all well and good but before anyone can agree no selection is better the problems of not selecting need to be addressed: Namely how to extract quality arguments from non-quality ones.