You would need to go back to the days of Bill Nicholson. We were a top tier club that signed top tier players and when those players left us it was because we were done with them.
The classic example is Jimmy Greaves. Signed in 1961 for a then record £99,999 and sold to West Ham in 1970 in part exchange for the £200k Martin Peters. By that point, Greaves was past his best and it made sense to trade him for the best locksmith player in the game at that time and play Chivers and Gilzean up front. It bought us a few more years at the top and I'd say 3 trophies in 3 seasons vindicated the decision.
In truth, we probably lost that status when we were relegated in 1977. We bounced back with Ossie and Ricky but we were no longer the Big Fish and we started losing players on their terms rather than ours.

