Also, for every player that was bought cheap and makes it through the ranks, there's more that didn't and are forgotten. My short answer to the OP is that it's definitely still possible in the short term but in the longer term the money will show and the best players that have propelled the "normal" team to their current standing will be picked off. You might get one or two that stay loyal but it'd be miraculous these days to put together a squad of top players and they all decide to stay at a club on lower wages. Rooney was at the biggest club in England but he was happy to risk derailing their season by asking for a transfer to get more money until he got offered the extra money he was demanding. He might be a twat but he's in the majority when it comes to football players.
I think both Piskie and Jayram are right here and the degree to which each is right is going to be very difficult to determine. There are good players out there, but finding them is more difficult than ever. Arsenal no longer have the monopoly on scouting Europe. In addition, the financial clout of the rich clubs bites here too. Because the rich teams can sign your players away as soon as they are a success, you have to sign ALL your prospects to long contracts and to do that you have to offer them high salaries. So if they don't work out, you are saddled with 10 players not good enough to play earning 50K, and nobody wants to sign them. I don't think this season proves very much in respect to Arsenal. Whether the transfer window was bungled or whether it was just bad luck, we will never know. But we were doomed from the start. I think this next year will be Wenger's last, in his curent capacity, if he doesn't win. I think we need to get a good pre-season, you can't change tactics or organization very easily through the year. It was a miracle that we were able to do as well as we did. If we can get some depth, and a fast start, and get a few young players stepping up, then we can win next year. We are not as far off as the points gap might suggest.