Well, the Kings immediately nose-dived and the player in question was sent home at one point and then eventually bought out. So it wasn't a good signing and was, in fact, a bad move. No other team was willing to give him the 3rd year because even the two years was risky. While sometimes the simplest answer is the solution, it is a move that doesn't appear to have much thought to it, i.e. "We can't score enough so sign a guy who is a great scorer" but it doesn't factor in how old he is (is he actually still a great scorer?), how he fits with the roster, system etc. You can still like Kovalchuk after his stint here but the move was a complete failure and is the avatar of Blake's complete failure to know what he had with this roster: he thought they were a player away but, instead, they were sending a letter out to the fans in January talking about how they are starting a rebuild.
It didn't cost the Kings a direct asset like the Lombardi trades but it did cost AEG a good amount of real dollars. When it comes to being able to buy a 1st round pick to eat Patrick Marleau's salary, the last-place and rebuilding Kings don't step up to the plate because AEG is sitting here paying John Stevens, Kovalchuk and Phaneuf to go away. If they aren't paying that Kovy money, maybe the Kings have an extra 1st round pick which is gold to a full-on rebuild. Instead, AEG is like "we aren't letting you spend any money for awhile here, Bowlby."
The reasoning argument is fine (we just need a goal scorer) but it was completely wrong. The reasoning for the Lucic trade was fine but it was completely wrong as well. Team won two Cups in three years and then missed the playoffs with a 95 point season from hell. 102 point season with Lucic but you had key injuries to Gaborik and Greene (3 games played total) with Martinez getting hurt before the playoffs being a real killer. If the Kings get the Gaborik they got in 2015 (27 goals) then that team would have been a legit contender. The reasoning was fine but the cost to acquire Lucic was the real issue on top of relying on Gaborik staying healthy and, really, near-perfect health since the depth wasn't there with Voynov gone.
DL should have kept the 1st round pick and sucked it up but, in all honesty, he sealed the "all-in" fate when he gave Gaborik the extension. The decisions to keep Richards and sign Gaborik meant that they were all-in from that point forward since the money was being spent and you really couldn't waste a healthy Gaborik season or know how many of them you were going to get. If they completely cratered in 2015 then maybe he chills out but they missed the playoffs by one point and were what felt like 2-80 in OT/SO. Very easy to believe in your guys that actually won two Cup for you and think that it was just a fluke season and everything is fine, just like it is very easy to keep the band together after the insane 2014 Cup: but he was wrong.
For Blake, it is extremely easy for a first time GM to inherit a core of dudes that won a Cup or two, do nothing and make it back it back to the playoffs to think that these guys aren't the 2015-2017 team but they are actually the guys that can still win a Cup. Like you are saying: it's not a big move or anything because he doesn't have to actually worry about "losing" a trade since he is just spending money. That is an easy move while actually taking over in 2017 and breaking up the band was the hard one. That 2018 team had a complete outlier year from Kopitar and the back-up goalies lost like one game which is super flukey as well. He bet on a dead count bounce that, much like the 2016 team, lost a lot of momentum down the stretch and--exactly like the 2016 team--lost the final game of the season at home to put themselves in a spot to get smoked in the 1st round to the eventual Cup finalist. Vegas exposed them and they didn't lose because of a lack of a one-trick pony goal scorer: they couldn't even get the puck out of their own zone to be in a position to get the puck to someone like Kovalchuk. But, since Quick played out of his mind, Blake looks at it like "we were in these games and just need some more on the power play". He wanted to believe that just like DL wanted to believe that the 2016 team was still the 2014 team. Shit...Blake wanted to believe that the 2018 team he had his first year was that 2014 team and just needed a little help up front.
Neither of them wanted to do the difficult thing which was start moving "made men". Blake didn't do it until the whole thing was in shambles and invited one more guy on the Titanic with $18MM of AEG's money shortly after committing $88MM to Doughty so the Kings could be a bottom feeder for the next three seasons and counting. Doesn't matter if the reasoning can be supported since this is a results based business and the results for both of these moves are horrible. Is one worse than the other? Of course; however, the Lucic deal easily doing more damage than the Kovy signing doesn't mean that the latter wasn't a "bad move": spending $18MM of your bosses' money on something that immediately bombs has consequences...they just as aren't easy to see as a highlight of Barzal/Connor or whoever else someone wants to say the Kings would have taken with the Lucic pick.