Several reasons.Many people don't like River's attitude and his lack of class he has displayed in the past. Yelling at crowds and so forth. Some just want to believe he is an ave qb that got lucky b/c LT had a poor year and SD had to throw more. Face it guy's a stud whether you like him or not. This is partly the reason he is undervalued.Many also over-evaluate a player's past success or lack of it against a particular team. Is it really relevant today what player A did against team B three years ago? Probably diff players, coaches, game plans than back then and all of the players if still there are older.Rivers was the #2 qb in my league's scoring last year, he's tough, doesn't miss games, great completion % and qb rating, he's in his prime and has some of the best passing options in the NFL. Don't overthink this stuff. You can't always predict football success by some matematical formula.For some players, football predictors just consistently undervalue or overvalue certain players. Many websites ranked Rivers 15th or so last year preseason. Ranked Garrard around 10th. I believe Rivers will continue to be undervalued and Garrard will continue to be overvalued. Until when and if Rivers wins a SB. Rivers may have a down game vs. Oakland this week. But to believe its b/c the Raiders always have his number doesn't make much sense. Always play your studs.