Brad Garlinghouse's peanut butter memo raged against Yahoo's redundant products. For some Yahoos, farewells are equally repetitive. Scott Gatz, one of Yahoo's R&D managers until he left last month, held a second goodbye party in Sunnyvale today, as boss Bradley Horowitz's Flickr stream shows. Some attendees were puzzled: Didn't this guy leave already? Just imagine what Yahoo could do if it put the same effort into building projects for the future as it did saying goodbye to the past.