Saturday's clash between two struggling sides at The Hawthorns looked destined to finish goalless until Allan McGregor picked up an Ahmed Elmohamady back-pass 13 minutes from time and Saido Berahino drilled home the resulting free-kick.
Berahino looked the only player capable of breaking the deadlock in a drab encounter, but the in-form striker's 14th goal of the season was something of a gift.
Hull played for just over an hour without a recognised striker after Nikica Jelavic and Abel Hernandez limped off with knee and groin injuries respectively.
Bruce's men look set for a battle to avoid relegation and the former Sunderland boss was left to rue a breakdown in communication between right-back Elmohamady and goalkeeper McGregor.
He said: "Away from home with the problems we had, particularly with the loss of our strikers, then you do take a point away from home.
"And to be perfectly honest it looked to have 0-0 written all over it, we were so comfortable defensively that it's a frustration to lose a game with a misunderstanding like that was cruel on us, but that's the nature of it.
"You make mistakes at this level, which we've made today, and it's one of those comical ones which to lose a game of this magnitude is hugely disappointed of course."
The Hull manager also spoke of his frustration at losing another two players to injury.
He added: "I don't know how many teams I've picked, over the last 10 games in particular, since day one with the loss of [Robert] Snodgrass, [Mohamed] Diame, Hernandez, [Sone] Aluko - the list is endless - and unfortunately when you've got eight or nine of your big players missing, then it does become a huge problem for us."
Jelavic underwent knee surgery in October and Bruce revealed the Croatia striker will be sent for a scan to discover the extent of his latest injury.
"It's not like him to come off, so there's something wrong," said Bruce.
"He felt it a bit yesterday to be fair to him and wanted to play, but he is not likely one to miss so we do fear it that it's something niggling away, we just hope it's not a recurrence of the previous injury, but until we get scanned we'll not know."
