Fighting Blue Tits

This amazing sequence of events was captured by the nestbox camera of a BTO Nest Recorder. The female incubating a full clutch of eggs is attacked by an imposter, presumably a second female. During the scrap, the male of the nesting pair keeps entering the box and attempts to feed his mate, oblivious to the commotion.

Is he just insensitive to her plight or just intent on carrying out his feeding duties, ignoring the female squabbles?