FLOWERY BRANCH — Atlanta Falcons coach Mike Smith was in a good mood after practice Saturday because his starting offense rolled Thursday night a 27-23 preseason loss at Baltimore, and it figures to get better today with the return of Pro Bowl tight end Tony Gonzalez. The 37-year-old Gonzalez participated in the first three days of training camp after team officials in the spring coaxed him out of a brief retirement. He then left with the team’s permission to be with his 12-year-old son, Nikko, as he began his youth football career in Los Angeles - keeping a promise he made while “retired.”