Will the New NASCAR rules make much of a difference?

I know stats pretty well, but the inner workings of the cars, not so much. In the new rules starting at Dega, the cars will have 7-10 more HP and they should run cooler from adjusting the cooling system pressure. My question is, how much of a difference will this make?

...The size of the restrictor plate that teams will use to prepare and practice for the race will increase by 1/64 inch and is now going to be 57/64 inch diameter. This will provide the teams with an additional 7-10 horsepower.

Additionally, the pressure relief valve on the cars’ cooling system will be recalibrated to reduce the pressure by approximately eight pounds per square inch from last April’s NASCAR Sprint Cup Series race at Talladega.

I think the premise is that the faster the cars go the more difficult it will be to hook up for long durations of time. That's my theory.

From what I hear on Sirius is this:

The change in the plate will give the drivers more throttle response which will give them the ability to pull out of line.

The lowering of the pressure in the cooling system means that the boiling point of the fluid in the radiator is lower. Thus, they will not be able to stay in the two car tandems for as many laps without pulling out and moving to a different partner or switching places in the tandem. Where now they could stay hooked up for about 8 laps it will now only be like 4 laps.

In a nutshell they will overheat sooner so they will need to switch more so they were given more horsepower/throttle response to make those moves.