Sagan's classics season is over and we saw that unlimited progress is not granted even for him. We saw him to be under his 2013 level and sometimes maybe even under his 2012 level (when he was more successful in sprints after long distances). Something was not right during winter and maybe his head is not ok as well (contract issues and health problems of his mum). But "thanks" to his worse form we are able to see his weaks (or points to improve) - last year's super-form was like masking agent. We discussed here several points and this is my summary after P-R:
1. Long distance is not his problem to be in the mix or to try something. In P-R he was able to attack alone twice with 35 and 20 km to go.
2. But his problem is sprint after long distances, he can't rely on his kick or speed after 250+ km. We will see later in the season what sprinter he really is in the shorter races (his sprint in 2012 was better than in 2013, but every season is different).
3. His weaks are hard cobbles sections at the end of the long races. He is regularly dropped on Oude Kwaremont. At P-R we could see Sagan making seconds on the road and subsequently losing time on 4* and 5* pave (headwind in both cases). This was mentioned already in 2012: "He sits high and forward, meaning his centre of gravity makes his bounce and often loses control of his bike on the pave." Of course, when you are in super-form, everything is easier.
4. I am not sure how to judge his strategy and tactic. Some of you mentioned he should conserve his energy more. His GM is essentially saying he was not smart enough during P-R.
I personally dont take this fascination by "new" Cancellara. I want Sagan to be Sagan and not worse version of Degenkolb, sitting-and-waiting-for-sprint-finish. Not even to say it wouldn't work in Sagan's case this year (see point 2).
5. His team support. Discussed many times. Too soon on his own on most occasions.