I pulled this anonymous question from a comment on a previous post here:
In CS3, when you try to align points, let's say u have a ragged line made with the pencil tool (of let's say 5 points), and then you want to align the points and select all of them with the white arrow tool, how does AI know if you want to align the points between themselves or the whole object relative to another one? I mean, when all nodes are selected, can Illustrator tell if u have selected the object or just all of its nodes? I've been told FH was able to tell the difference.
Illustrator CS3 introduced the ability to align individual anchor points using the functions found in the Align panel (or the Control panel). This question actually bring about something which appears to have somewhat changed in Illustrator CS3 from CS2. Or if it isn't a change in actual behavior (meaning that it did happen in CS2), it's something that we have visibility to that wasn't present in the past.
First, it's important to understand what the Align functions do. When you select several objects and choose to align them, Illustrator treats each of those objects as individual entities. However, you'll notice that if you select several groups, the Align panel will treat each group as an individual entity. Which is why you can't align objects that are within a group when you simply select the group (as the group is treated as one object). To align the objects in a group, you can of course, double click on the group to isolate it. Then perform the align, then double-click to exit the isolation. Of course, you can also use the Direct Selection tool to select a few elements within a group, and you can align those. But if you use the Direct Selection tool to select ALL of the elements within the group, the Align functions realize that you have a group selected. And once again, it's treated as a single object.
Now think of each anchor point within a single object as if they were individual elements in a group. As long as you have SOME of the anchor points selected (meaning, not all of them), then Illustrator allows you to align those points. But as soon as you select all of the point on a path, the Align functions don't see the anchor points anymore -- they see the single path (again, think of the group).
I've noticed that in Illustrator CS2, when you select just a few anchor points on a path, the Control panel lists the Path as being the target. But now in CS3, when you have just a few anchor points of a path selected, the Control panel lists "Anchor Point" as the target. Apparently, that's how the context-sensitive Control panel knows to display all the new convert, handles, and anchor functions.
So you would need to select all anchor point except one, perform the align, then select that last anchor point that was left out, shift click on any other anchor point, and then repeat the align to get what you want. It's important to select the anchor points in that order. You already know that to align to a specific object, you click on a key object once you've made your selection. Well, with anchor points, clicking on an anchor point after it was selected will deselect all other anchor points. So Illustrator uses the LAST anchor point you selected as its "key" anchor point.
With regards to FreeHand, yes, this is far easier to do there. That's because FreeHand has the ability to select all of the anchor points in an object without selecting the entire object itself. For example, if you marquee select your entire object with the pointer, the anchor points become selected, and you can align all of the anchor points in the object. Click on the path with the Pointer and the entire object becomes selected, and will align as a single object. I believe my good friend JET likes to refer to this as FreeHand's ability to select anchor points and paths individually, where with Illustrator, they seem to be one and the same.