We have seen the good and the bad, but that is only part of the story. The Padres did not just get Matt Kemp. They gave up stuff to acquire Matt Kemp. The gave up stuff to the Dodgers to get Matt Kemp. The gave up stuff to the Dodgers to get Matt Kemp which helped their rival alleviate a log jam they had in the outfield. The Dodgers lost Matt Kemp, but they had ready made replacements. In addition to having an outfield Andre Ethier, Carl Crawford and Yasiel Puig, they also have a top prospect in Joc Pederson and some capable bench bats in Chris Heisey and Scott Van Slyke. The Dodgers could afford to lose Matt Kemp.
And all that is without considering that the Padres filled another hole for them at catcher with Yasmani Grandal. That is Yasmani Grandal that is projected to break out. You can find people writing about that here, here ($), here and here. He already began to do just that in 2014. He played in 128 games last year despite recovering from a knee injury that was supposed to have him miss a good chunk of the season. His On Base Percentage was second on the team at .327. A modest mark, but very nice for a catcher and over 100 points higher than his batting average. That's some real on base skill. It could be much higher if the baseball gods smiled on him a bit more since the stat (BABIP) that checks if balls are dropping in at a normal rate was a good chunk below average. He also slugged 15 HRs, which isn't overly impressive, but considering the injury he was coming off of and the lack of experience against major league pitchers going into the year it seems like the sign of much more to come. It's also worth noting that his numbers were dragged down by a sluggish start. One that likely had to do with that injury recovery. His second half was very good. Especially for a catcher.
That isn't to say that Grandal will be a future All Star (although there's a chance). He doesn't have to be. When you total up the good and bad for Kemp, he doesn't play at an All Star level anymore either. He hits like one, but his overall value isn't there. Grandal seems really likely to match that kind of value. And he would do it for way cheaper. And now he'll do it for the Dodgers. At a spot where they were lacking other quality options. The Dodgers. The team the Padres have to finish with a better record than in order to win a division. One that on paper, even if Kemp were an All Star, stacks up way better than the Padres and adding Grandal only helps that.
On fangraphs today, they compare this trade to the Angels terrible trade for Vernon Wells. A player whose best days were behind him, couldn't play CF anymore, but had a name and a hefty contract. The Angels took on that money and got a player that couldn't come close to playing like he had in his glory days. They gave up Mike Napoli, a sort of catcher who had some great years ahead of him at nowhere near the cost of Wells. Hopefully that doesn't turn out to be the case for the Padres, but it has all the makings.