Everyone's waiting for that example. That's why it's so hard to see any.
That stuff about being half as good if you work on two things simply sounds good as a thing to tell kids at school, but amounts to nothing. A bowler could be attacking, and a big turner of a ball bowling legspin, and bowl offbreaks when his role is to tie up an end. I can think of any number of such possibilities. However, we dont see any out there because of entrenched attitudes, basically starting out from the first coaching experience where the coach asks a youngster what he wants to do- bat or bowl, and then whether he's a spinner or paceman, leggie or offie, and then train him on one thing. It will work for the majority of people but you'll lose the rare guy who can actually do two things. Sure the coach has to be carefull about this and use judgement, but they should always give talent a chance.
About doing two things, how come allrounders survive? How about a player like Gary Sobers? It's more about breaking out of a cast than some obscure theory. Every player needs to 'be practiced'.
BTW, will the point that a person cannot do two things become wrong if you suddenly have a player on the international arena who can do what Sachin does consistently? If that's the case, then there's no logic behind arguement.
Rik, of all the different things Sachin can do with the ball, medium pace is what he least often does. I really don't think you've had a chance to see him bowl too much! I've seen matches in which he's turned the ball as much as Warne and been more effective. Because of his idea that he should stay on as a batsman who can bowl he's never going to be consistent. But he's not just another part timer. I've seen enough of him to be convinced that he's one of the biggest turners of the ball around, both ways, can bowl a very good googly, and is a good attacking spinner.