This process is powerful but cumbersome, with confusing nomenclature. Surprisingly, you can't turn off attributes temporarily in the Appearance palette. Illustrator has creative, fine control over effects. For instance, you can isolate Blend modes to affect only the colors in a user-defined group of objects. When Knockout is turned on for a transparency group, the uppermost object blocks the other objects in the group, but the transparency feature shows objects underneath that are not part of that group.
Illustrator now features opacity masks.
The gray scale of any object may mask what you see of underlying objects. Though rather clumsy, these powerful opacity masks are much like alpha channels in Photoshop, in that they can use any gradient, pattern, or image. The big difference here is that Illustrator's masks remain editable paths and fills. Layers management now has the added ability to nest related layers and also display thumbnails of layer content. Clipping masks can be created with push-button ease to define the uppermost object as the outline through which all other objects on that layer are seen.