Smith’s struggles in San Francisco mostly stemmed from two issues -- the first being a parade of unsuccessful coaches and offenses. The second factor was inconsistent snaps. Smith has played a full season only twice -- in 2006 and 2011. Aside from those years, the most games he played in a season has been 11. He had been in and out of the starting lineup in his first few seasons in San Francisco.
Smith's performance received the largest boost under Jim Harbaugh. His completion percentage, yards per attempt, and quarterback rating were all at their highest levels and not by close margins under the former Stanford coach. There is no reason Smith can't maintain his recent performance under Andy Reid. And there is no reason Bowe won't be able to perform comparably to his past performances under Reid.
During his time in San Francisco, Smith turned to running back Frank Gore and tight end Vernon Davis just as much as his whoever his top wide receiver was in that given year. Gore and Davis have always been at the top of the 49ers’ leading receivers list. Smith’s favorite weapon in Kansas City very well may be running back Jamaal Charles.