I still don't believe that drivers will (on purpose), run 4-5s slower than the pace they are truly capable of. Certainly, Hamilton will not resort to doing this as he doesn't know any other way of driving, except for 'eye-balls-out' or 'balls-to-the-wall' (I love that phrase).
If anybody is capable of driving slow, it has to be Button, so I guess he will be the one to watch. If he does not resort to driving ultra slow (on purpose), then I can't see any other driver on the grid following the drive-slow tactic.
One thing's for sure, if some drivers on the grid choose to drive ultra-slow, Hamilton will rip past them and take the hit of an extra pit stop. It should make it exciting in that we will see 2 different strategies played out. This is bringing us back to the old days of 1 stop vs 2 stop refuelling strategies.
PS. The more I think about it, the more I'm wondering if Mercedes actually do have the fastest car on the grid. The last time we saw BrawnGP/Mercedes finish off testing in top spot, they won the World Championship. This year, Mercedes finished the last test in top spot. Ferrari certainly have the reliability, but Mercedes...I'm not sure. I can't believe that MSc is happy to finish another season as an also-ran.