In bug 18532 we add a messaging preference for the auto_renew notice. It would be good to do the same for the regular renewal notice. Right now, patrons get a renewal notice if the RenewalSendNotice syspref is on and the patron is signed up for CHECKOUT notices, with RENEWAL just following the CHECKOUT preference. That assumption -- that if one wants a CHECKOUT notice one must also want a RENEWAL notice -- is both spurious and largely undocumented.
Sorry, I need to walk back a bit of my snark here -- I forgot that we have updated that messaging preference so that it says "Checkout and renewal" in the preference. So at least we're telling people there what it means. But I'd still prefer a separate preference.
I agree it would be nicer to have them as separate options - changing the descriptions was just in shorter reach for the time being.
So having the renewals notice preference attached to the checkout/checkin preference causes patrons to get a duplicate notice about renewals if they have both Item checkout and renewal and Autorenew notices turned on. We only just noticed this recently, because we are now using messagebee, and they handle both the RENEWAL and AUTORENEW notices as the same thing, so it really looks like a duplicate notice. Emails had different wording, so it wasn't as obvious. I assume the workaround is to have patrons choose between getting all three notices (checkin, checkout, renewal) or just autorenewals?