Redknapp splashed the cash in January to try and avoid the drop with £8million spent on France forward Loic Remy.
It is a piece of business that has appeared increasingly more astute after Remy scored in the successive wins that have revived QPR's survival bid.
The west Londoners have hauled themselves to within four points of safety ahead of Saturday's relegation battle against Aston Villa, who sit in the final safety position.
Villa have themselves relied on Christian Benteke's 12 league goals to keep them afloat and it is a similar story for all the clubs in the bottom six places.
Southampton striker Rickie Lambert has netted 12 times in his debut season in the top-flight, Sunderland's Steven Fletcher has 11 while Reading's super-sub Adam Le Fondre has managed 10.
While Arouna Kone has managed just eight for Wigan his double at Reading last month inspired a crucial 3-0 win.
"Everyone needs their strikers," Redknapp said.
"If you'd have taken Fletcher out of Sunderland's team this year or Benteke out of Villa's team it would hurt. You're relying on strikers really.
"Unless you're Man Utd relying on four great strikers that is different. At most clubs, if you lose your two front men then it leaves you (in trouble).
"There is nothing worse than when you're sitting there at 0-0 and then they score and it is game over.
"I've been through that before. I went through it a long time ago at West Ham.
"If we went 1-0 down we might as well all have gone home because we had no strikers.
"We were going to get relegated in my first full year. I bought (Paul) Kitson and (John) Hartson in and all of a sudden we went on a run beating everybody and every week they scored."
Redknapp believes it was QPR's lack of strikepower at the start of the season that has left them in their relegation scrap.
QPR suffered the longest winless start to a Premier League season to prompt Mark Hughes' axing, but Redknapp believes the Welshman was undone by injuries that robbed him of Bobby Zamora and Andy Johnson.
"I think Mark was just unlucky. The biggest problem for Mark was he lost his two strikers," he said.
"If they could've stayed fit I think it would've been different for him. You need a bit of luck in this game
"I think that had a big effect on him. That was an area that was a problem, we were short."
Redknapp's solution was to bring in Remy - who has scored three goals so far to earn a recall to the France squad this week.
And with Zamora also starting to put his injury problems behind him the goals have come.
QPR scored three goals in a league match for the first time this season in their 3-1 win over Sunderland last weekend to enthuse their boss.
"All that's changed is Remy's come in and started scoring and Bobby's come back fit," Redknapp said.
"It's made a difference to the team. We look like we might score.
"Beforehand it was 0-0, 0-0, hanging on trying to nick a point, but with those two, if they can stay fit together, then that's great.
"Plus we've got Jamie Mackie who worked his socks off last week and we've got Jay Bothroyd who does a good job when called on."
Despite QPR's recent improvement - they have lost just twice in nine league games since the turn of the year - Redknapp admits beating their relegation rivals will play a decisive part in keeping them up.
By his own admission the trip to Villa Park will be "big" and it is hardly surprising he has targeted Benteke as the key man his side must stop.
"He's been outstanding, he's had a fantastic season," he said.
"It's a big game tomorrow.
"Hopefully the experience we've got of being in big games will help.
"We've got some big-game players here. Hopefully tomorrow that will be in our favour."