As I see things an entry on the MR unarguably satisfies the obligation to "report all defects".
A PIC is required to read the MR and make proper allowances for any/all defects or required maintenance listed thereon prior to flight. I mean, for example, that a failed nav light is reported, as it should be, but you as PIC ignore that coz your flight will be day VMC.
Knowledge that the next flight will not require the item to be entered on the MR is not a legal mitigation. Things might change so the law proscribes your using this knowledge.
Practically speaking, you'd be pretty dopey to not mention to the owners that there are new entries on the MR.