Every year it's predicted we'll fall out of the top 4, it never materialises. If we lose Fabregas and Nasri, I'm sure they'll be replaced in some form. Wenger's not mad - he'll sign a couple of players if they both leave. If we're being honest though, Nasri won't go this summer.
Goalkeeper isn't going to be an issue for 20 years. Left back will be our biggest problem, and I don't get why that hasn't been addressed. Centre-half could be addressed too, hopefully not with a clogger like Samba.
We've got problems, but you're exaggerating when you say 6th. We're better than Spurs.
It's the first time I've predicted it, you've been in a gradual decline since 2005.
09/10 you lost Adebayor and Toure, both of whom would still be of use to you.
08/09 You lost Flamini and Hleb, again, your squad could still use, maybe less so with Hleb but you still needed him at the time.
07/08 You let Diarra go. Not sure on the circumstances but he would be a fantastic player for you now. He's a better player than Song.
That's 5 players who could still play a good part in your season. The difference between Wenger and Ferguson? Ferguson recognises the right time to release a player. With the mixture of the experience and quality of the above players in last years squad, you'd have made a bigger challenge for the league.
By letting Fabregas and Nasri go, you're only losing more experience. There's no continuity in your squad, you'll have a squad of players who have collectively won 0 Trophies in the English game. There's a few who have won domestic titles in the French or Dutch league, but it really doesn't equate to much.
Look at how continuity helps United:
Anderson, Smalling, Evans, Rafael, Fabio, Hernandez and Macheda all have Premier League Winners medals, some multiple. They know what it takes to win it. Some have played in UCL Finals against the best players in the world.
They have learnt what is needed to win from players that know how to win, because Ferguson keeps players and lets his youth learn not only technique but the mental toughness and attitude that is required to win from his team of winners.
Every time you sell a player that has built up experience playing for you, you take a step backwards and that's what Wenger has done for the last 6 years, 1 step forward and 2 backwards.