To dominate, Mercedes needs to improve its race pace. That has to do with keeping the tyres alive, but in addition I think they are also often slow at the beginning of a Grand Prix, that is, before you would expect overheating rear tyres to come into play (for example, Rosberg knowing by the third corner in Barhain that he wasn’t going to be able to keep Vettel and Alonso behind).
Intuitively, it feels easier to improve race pace than to improve qualifying pace, yet some patterns, like Mercedes being fast in qualifying versus Lotus and Ferrari being quick in the race, have persisted for quite some time. Hence, fixing race pace is no easy thing, and they need to fix it before they can start to think of dominating. Their season so far, from competitive to not:
3. Malaysia: had the pace to challenge for the win.
4. China: once Lewis had gotten rid of debris in his front wing, he was pushing Kimi for 2nd.
5. Canada: a podium for Lewis that was helped by Nico holding up Webber initially (and thanks to VdG, of course)
6. Australia: super softs worked reasonably well after the first few laps, but on mediums they didn’t have the right balance.
7. Germany: initial pace on the softs was actually pretty good, but the mediums didn’t work until the final stint.
8. Bahrain: the car was a dog until the final stint.
9. Spain: the car was rubbish throughout.
Also, I’m not that convinced that the Mercedes really favours the hard tyres over the soft tyres, as they struggled most on the hardest selection of tyres in Bahrain and Spain (where of course it was hottest). Isn’t it true that the softer compounds have a higher working window?