I'm not sure what's up with the Lincy deal honestly others are probably more qualified to offer insight on that.
Yeah, seems like an overpay to me too for what is /ideally/ going to be a #3 starter for the next 2 years while Crick and Blackburn get developed. My thinking on this (aside from the kneejerk reaction that the Giants are dumb and do dumb things [like sign Hunter Pence to multiyear deals]) is 2 things which happened simultaneously.
1) The Giants have big needs. This became very apparent this year. Cain and Bumgarner are fantastic pitchers, and when Vogelsong is on, he's pretty damn on as well. Buuuut when they aren't the team turns to crap. We don't really have much depth, or at least, we don't have the depth it seemed we did 3 or even 1 year ago. This goes the same for our outfield. When you're having to rely on Pence, Pagan, and a revolving door of career AAAA players as what can only laughably be described as "a platoon", you have some serious problems. This issue is multiplied because
The Giants effectively do not have a farm system. Brown is a bust. Panik may or may not be heading in that direction too. Hembree, Pill, Perez, Kickham, etc. are never realistically going to be more than 5th starters/bullpen/bench players, and the better of those have been struggling with injury issues. The core of our system - Crick, Blackburn, Bond, etc. are all in High-A ball and are realistically 2 or even 3 years away from seeing big league play.
2) The Giants didn't finish in the bottom 10 this year. Ostensibly the plan (which Sabean confirmed back in September) was to slide into the bottom-10, QO Pence and Lincecum, sign an outfielder (probably Choo), see what the market had for pitchers, and hopefully snag two choice 1st round draft picks (or at the very least sign Pence and Lincecum on the cheap during Spring Training). But the Giants didn't finish in the bottom-10 so the already bleak free agent market (seriously, who we got? A Halladay who may or may not be able to actually throw a ball...and don't even get me started on outfielders) became even bleaker. So the Giants got desperate and since their budget was set to increase by 20-30m this year, Lincecum and Pence suddenly became
very important to the Giants staying relevant as a team and keeping that sellout streak going. So they overpaid on both of them...and the Giants will essentially be putting the same product on the field that netted them a 76-86 record. Awesome.