That's your view and you're entitled to it. But where you may be missing the point is that it has nothing to do with "surplus cash available" it has everything to do with overheads of which the wage bill is the biggest component.
Fergie doesn't lie but he also doesn't reveal all that is going on to the media either. He's a master at disinformation when it suits him - let's put it that way. His main communications on these matters are with the media, whom generally he hates and not the fans per se. He's certainly not going to come out and say "I am restrained by the club's wage policy and that's why we weren't able to get in players who could immediately improve the team in the summer and not just investments for the future" - or words to that effect.
Oh yeah our delicate wage structure, those tight restrictions being placed on us which have seen Rooney handed £200k a week, Evra £100k and even John O'Shea £80k; tight bastards!