We’re told this could be a Photokina 2014 lens
Boys and girls(any?), this is a [CR1]
wild guess and be explicit: This lens would only be announced
in end of September, 2014
, more than a year from now...
... and by then it won't be in mass production but available in limited quantities, after all they're producing it not only for the Canon mount and new lenses always take time to be available everywhere.
And here I am, just having bought the Tamron 24-70 VC not a year ago...
The date and a high demand make very suspicious if the price
could really be less than Canon's mk2, after all the Canon's price will have dropped in the meantime and even more facing real competition if the Sigma's af is better than Tamron.
Plus of course
be large and heavy
, it's not like Canon wouldn't be able to build something like this, they just gave in to pro photographers' demand with their mk2 to *reduce* weight rather than to build an impractical dream lens for moving about and handholding a long time: [CR1] doesn't change the laws of physics...