When it comes to Red Sox GMs, being decisive, going all in on free agents or trade targets, is perhaps a most important trait. Spending really isn't the issue, but who they spend it on.
Duquette landed Manny, Pedro, Damon (among others) -- and no one thought they weren't worth the investment.
Epstein spent like a drunken Dombro, hit or miss -- for every Schilling and Foulke, there were Camerons and Gagnes -- but when he didn't want to keep a Cabrera or Renteria or Lugo, he never stopped, adding an Alex Gonzalez or Stephen Drew... Todd Walker became Mark Bellhorn -- get back, Loretta... Kevin Millar was going to Japan, but Theo redirected his flight.
Cherington collected a lot of good vets that coalesced together to win a title. But his later acquisitions were bad fits: Hanley in left, Rusney in the majors, Pablo anywhere in a Sox uni...
As a GM, Bloom was maybe most similar to Ben (sans the ring). Both were tasked with huge salary dumps, and Chaim's big expenditures, like Story and Yoshida also look like awkward investments -- so far.
But what separated Bloom from his predecessors and made him an ultimate failure was his inability to lock down better bets with market value contracts, or swing deals for others under control by parting with prospect capital. Some might blame ownership on his roster-building. Then again, isn't his roster-building the reason he was fired?