Well, where can we look to find out? Do we have any members that use the DCCD to such a detailed extent on here? I've read about it, but I didn't quite understand it all. I'd think with a 'trial and error' experience, you'd understand it more. I've only used it once on LOCK two winters ago. I was stuck in some deep snow and couldn't budge by going forward and reverse. Once I put it in LOCK, it only took a matter of seconds getting out.
Try this out:
http://www.igotasti.com/vBforum/showthread.php?263-DCCD-info-and-FAQs&highlight=dccd
Most likely he was in manual mode, unlocked with the rear at full biased.
Go out for a drive and play with the settings. I have and have a better understanding of how the car acts with each setting.
Auto modes are basically the car giving you a bit better driving experience for conditions and wants/needs. The auto function still maintains the functionality of the DCCD but allowing the user to have a bit better or different experience based on their style, wants or needs when the situation arises.
Auto (normal): You can feel the front end work more in the turns and when on/off throttle. Generally this mode is good for all around driving in most conditions. It is also acceptable in winter conditions. Biased is the 65/35 until the diff adjusts when needed.
Auto (+): This is a bit more front biased meaning the front end will be working more than in it's normal operating state. This mode tends to make the front end work more and you can feel this when on/off acceleration and when cornering. This mode is intended for more wet and slippery conditions. This mode is what I primarily use when the roads are slick and I don't want to have any tail happy moments. The feeling is somewhat more like a front wheel drive car.
Auto(-): This mode is going to be more rear biased. You can feel the front end work less when on/off throttle and when cornering. The car feels slightly more rear happy and you have somewhat of a more rear wheel drive car feeling. This mode is used most often by me when driving in normal or dry conditions.
Manual modes have a very different feeling. At Manual with no bars, the car definitely is more rear biased. During on/off throttle and in the turns, you definitely get the impression that the rear is in more control. You don't notice the front end compensating or working near as much as the auto modes. This mode os very fun for me and I have tendency to use it when I want some fun.
As you increase the bars to full lock, the feeling changes to a more of a traditional 4x4 feeling. The steering gets heavier and you'll notice pops and groans at low speeds. Rut grabbing or tramlining is also more prevalent as you get closer to lock. I have used it a few times in snow/dirt/mud and it is very useful. Trying it out on dry pavement is more of an unpleasant experience that I don't recommend unless you need it. The whole attitude of the car changes and can be difficult to react to it most immediately. The steering is jerky and a lot of steering input is needed. If you have ever driven a 4x4 Jeep or something similar, and with the 4 wheel drive engaged on dry pavement, you'll get a very similar experience with the Subaru in lock mode. Basically, because the transfer case of a 4x4 only splits the distribution 50/50 and with no varying degrees. The Subaru in full lock will perform similarly to the transfer case type setup.
You should never drive a 4x4 with a trnsfer case on dry pavement at speeds and "locked in". This can cause damage to the driveline and cause for accidents as the handling/steering is greatly affected. Throw a locking front differential in the equation and this is disaster. I believe the Subaru to be similar and thus do not operate the system much passed the manual and rear biased settings on dry pavement. Plus, there is simply no need to do so as this will not gain you any benefits.
Oh, and to basically answer the question of vehicle attitude, the DCCD in auto modes will try to keep the car under control, not sliding and drifting, at whatever threshold limit it is designed to do. It is sort of a well thought out nanny.
Hope this helps.