The plan was to:

1. Clear out big contracts in order to clear salary cap space for the future and clear roster spots for younger players
2. Sign veteran players to short term contracts with a view to flipping them for draft picks at the trade deadline 
3. Draft and develop players from within the organisation
4. Create a team with talented young players who are going to be cheap in the short term in the knowledge that the cap space created by trading or otherwise shedding older players on dead weight contracts will be available to pay them well once they hit RFA status. 
5. Avoid trading youth for overpaid veteran players for short term benefits

They have done all of this to date. The time frame depends on how quickly young players develop.  Right now they appear to be developing ahead of original expectations. I would suggest to you that  no other team in the league has improved to the extent that the Leafs have this season.