Is this type-related, or is it just an annoying [imo] quirk?

My dad [LSI] has always done this: when watching a movie or tv show, he will always "predict" what's coming up [he especially seems to get a kick out of it when it's something he alone has seen before]. He doesn't care at all that it annoys my mom, brother, and me immensely; he seems to really be proud of himself Ni-HA?