Original post by KingMessiYes, this articulates a number of my opinions on Chelsea (and football more generally) very well, especially the last comment. I remarked to my friend that our 2012 Champions League win was the best and biggest of a number of opportunities to take on the 'United' mentality - that is, to really explode as a club that teams didn't want to play at all, ever: a team that had games that could be considered 'home bankers', etc. We'd had opportunities of this ilk before - the early Mourinho years and the 2010 Ancelotti side - but none on the scale of the CL win. Given that the Munich triumph was followed by the signing of some of Europe's most desirable and talented youth (Hazard, Oscar), we really had an opportunity to go into games always on the front foot, always looking to put teams to the sword. This just hasn't happened, and whilst identifying the issues is easy, understanding, delineating, and resolving the psychological and tactical problems that lead to these issues seems almost impossible.
To elaborate: one big problem is our tentativeness, and our willingness to just sit on a 1-0 lead. However, we don't 'sit' on a 1-0 lead in a manner that inspires confidence, as we did in the initial Mourinho period. There is a difference between dealing with a 1-0 or 2-1 with confidence, which involves playing predominantly in the opponents' half, holding possession, and stifling all life out of the game; and the converse, which is sitting on the edge of one's eighteen-yard box and praying that nothing goes in. We currently do the latter. This is easily identifiable. Less easy is postulating ways of dealing with this issue.
Another problem: we don't put teams to the sword. This can, in one respect, be put down to the mediocrity of our forwards. However, I am, of course, not the only person who will have noticed the way we retreat after taking an early lead (Crystal Palace was the most recent example, but others are not difficult to come by). The Ancelotti side continued to press for more goals, and kept the play in the opposition half after scoring.
This conduces to the third major problem: we never start to play with urgency or quality until the game is on the line for us (see West Brom at home, Tottenham away, among others). This is a really big problem, because trying to instantly alter the momentum of a game is very difficult, and if, as happened in the West Brom game, the goal goes in midway or late through the second half, there is not much time to gather the requisite momentum to take the win. Thus, we end up scraping draws or clumsy, tentative wins.
These all seem to be largely down to the mentality issues discussed by the above poster, but it isn't an issue of having more physical players. We have the talent to do very well, but we somehow need to instill not just generic 'belief' into the players, but a very specific belief: the belief that Chelsea are a club that should start games as heavy favorites, that it is a club that both can and should bully smaller sides, and that the players should perform with more freedom and license.
Now, I am the first to be censorious of bashing the manager, because he's the easiest and most obvious target - but I can't help but wonder how much of the restraint is down to Mourinho. He's always been a predominantly cautious manager, and that propensity doesn't seem to have altered (as shown by his dropping of Mata, ostensibly because he doesn't offer much defensively). Now, whilst I don't want to fall into the 'armchair fan' trap of suggesting that I could do a superior job to a qualified manager, I certainly think that, were I Mourinho - especially for home games against weak (er) sides - I'd want to set a marker down before kick-off by starting Oscar, Mata, and Hazard, and getting them playing in sync as a three, in the hope that this would put the entire side into a position of attacking impetus from the off. Mata and Hazard especially seem to have the 'dominate' mentality that Suarez and Aguero especially have, and Oscar certainly looks like he could get there soon.