Even though you need to be an insider to read the entire blog entry, you can read the opening blurb on Griffey. Apparently he had surgery on his knee, which had prevented him from using his legs effectively. There seems to be a belief that Griffey could have a rebound year if healthy.
In the part of the blog that you can't see, Olney suggests the Mets will only be scraping of the bottom of the barrell, which would net them someone like, you guess it, Griffey.
Now, if the Mets are going to be stubborn and not pony up the cash for someone like Dunn or Manny, I wouldn't mind them bringing in Griffey to play LF, with Tatis spelling him a few days a week to keep him fresh. Then, Murphy could begin the season in AAA, where he could play 2B everyday. This way, when Castillo finds himself on the bench due to injury or ineffectiveness, Murphy can slide into 2B, and we won't be subjected to Alex Cora playing 2B on a daily basis.
Honestly, it doesn't have to be Griffey either. Just bring in someone who will be an upgrade in the corner over a Murphy/Tatis platoon. Just a thought.