The reasoning that we DFAd Valencia from my understanding is that we're making another roster move after the game today that will result in us optioning a pitcher to bring up an OF. They wanted to keep the long 'pen as Dickey is going on shortened rest and there's a good chance that because Valencia was done on August 1st he's on revocable waivers (though I may be wrong on that) and there's a good chance instead of him being traded for 20k like generally happens he may be traded to someone for 500k.
The plan going forward will be to have Pillar, Bautista, Revere and a 4th OF (Pompey) going forward with Travis, Smoak and Cola (platoon) Goins, Donaldson, EE, Tulo going forward.
I think that it was the wrong move and that Cola should have been let go with Valencia kept as he has a lot more utility.