I still maintain that they did (aside from Gaston and Ben Afra on loan, both of whom I questioned at the time). Losing Snodgrass for the season shortly after signing him was massively bad luck, whilst Diame has been injured for quite a bit of the season too.
If those two were fit all season, I'm sure Hull wouldn't be where they are. But instead they've had to reply far too much on the likes of Quinn and Meyler, who are simply not good enough for the PL.
That said, the signing of Hernandez has just not worked. Maybe if they hadn't sold Long (but given the offer we made them, they had to accept) or if they'd signed N'Doye in the summer rather than in January, they might have scored just a handful of more goals that could have made all the difference.