Sorry to conterdict you but to steer the rear wheel the way Marquez does on the RC, you need more weight on the front.
The M1 is not as balanced as it used to be when Rossi was developing them, Lorenzo needs more weight on the rear wheel and it comes with its sets of problems.
First of all, you can't build up heat on the front tyre for hard braking, this last year brought grip problems to Rossi, also the large difference in temperature between loads (straight line and hard on the brakes) means the rubber have to work harder.
Then the rear wheel bias weight and inertia means that when the rear goes, there is not enough weight on the front for good steering authority, have a look at slow motion videos of his crashes from 2001 and you will notice this.
Every single time his M1 got out of shape on the gas, Lorenzo lost the front wheel a fraction of second later, this doesn't happen with a front which is loaded, you have better heat build up for hard braking and can manage weight transfer while retaining steering control, which is the actual M1 issue.
Rossi can brakes harder with the 2014 chassis, but they can't get the grip they need on the rear by changing position on the bike the way Marquez does with the RC, because they can't slide it as much, it still needs to be ridden on the edge of the tyre to carry more corner speed, there is less rubber, degrading faster, the temperature range is not ideal for the rear tyre either.
The best Yamaha chassis were developed by K.R as a rider and manager with the help of Rainey, despite a few difficult year, and later by Rossi and Burgess, they were more balanced than Lorenzo/Zeelenberg chassis, could be slided and still carried more corner speed than the Honda and Suzuki.
Now you don't see Rossi sliding the rear as he as doing in and out with "his" chassis, especially on the brakes, they are getting there but it is still biased for Lorenzo style, reason for their grip issues with the same tyres than the Honda.