What is the reasoning behind massively wide bars?

Back in the day we shortened bars to ridiculously short widths

I still ride with narrow bars

Quote Originally Posted by PeteS View Post
I do a lot of climbing on the bike. Mainly short , sharp stuff but seldom am I in the drops. That is is reserved for longer descents or for putting the power down on the flat i.e. situations when you need an aero advantage.
I've got straight bars on my 29er but I had to take an inch or so off them as they were just too wide so that's another consideration it you are thinking of changing.