What is Sehwag going through right now (for the past couple of years), if not an extended run of form - a triple and a 293 included? As mentioned Sehwag's career is very much work in progress (and Sehwag Mk2 is both more lethal and more mature than Sehwag Mk 1).Not true. The ball was doing a bit off the pitch and in the air through that series; represented by the fact that Hayden made acouple of low scores, but once he got his eye in, he did make runs in tough conditions during that series. His 94 in the First Test, especially was on a minefield, where all others struggled bar him and Punter.
Langer got cleaned up, but it surely wouldn't of happened if it was on a featherbed like you're suggesting; not so much that he'd need to retire hurt either. It was questionable if Langer was ever going to play again because of that blow.
Symonds was cleaned up by a bouncer that decked back off of the pitch and hit him flush in the mouth; cracking the grill and busting his lip open - requiring stitches. He couldn't even remove his zink cream for days because of it.
No, the difference between Sehwag and Hayden is that Hayden has made runs in favourable seaming and spinning conditions whilst Sehwag has only done the latter.
I doubt Sehwag will ever go through an extended run of form like Hayden did between 2001-2004 where he was literally unstoppable and almost scoring a 100 after every second match he played. At that point in time, Steve Waugh was comparing Hayden to Bradman.
As to Hayden doing well in seaming conditions, there's about a thousand pages of discussion and his stats in Eng,NZ,SA that I wouldn't be able to add a thing to.
[ Sehwag, like Indian batsmen, loves Australian pitches where most of Hayden's exploits have been. Averages more in Australia than himself at home and Hayden in either Aus or Ind.]