Yes and no. Not all AWD is created equally. There are systems with fixed torque split and electronically controlled torque split. Fixed systems have the torque split fixed at a certain ratio, like 50/50 or 30/70. Things like audi quattro and subaru AWD. Electronically controlled systems do what you've described, have the torque fixed at a certain ratio, like 100/0 or 70/30, until slippage occurs and it goes to 50/50. The G35X has a really good trick AWD system that they lifted from the old Skyline GT-R. It would vary the torque from 0/100 to 50/50. It was so good and seamless at doing it that many believed only the car was fast and not the driver.
And yes, btw, it does make a huge difference. The Haldex systems like they have on the Volvo have 100% fwd bias until things get spinnning, and you'll find that kind of thing on almost every crossover ute out there. XDrive and the G35X have a rearward bias and fulltime slip. As Raven sez only Subaru and Audi have fixed ratios. THe payoff for fwd 100% bias is better fuel economy but the 'feel' in driving is not nearly as nice (usually you end up with major push and you can't really 'play' the car at all). Subies and Audis and the rear biased vehciles are generally much more fun to toss around and safer dynamically as they are more predicatable and you do not have unexpected transitions. One of the reasons I decided to go w/ my new Outback XT.