Contradiction in XOR Evaluation Order Documentation

Question

This is more of a PSA post rather than a question, but I thought I'd put it up here to a) help anyone else out who is confused by this and b) hopefully get Appian's attention to fix this (I will also make a support case for this issue).
This is regarding how the XOR node in the process modeler evaluates multiple conditions. Looking at how the Decision tab is laid out (with IF...ELSE IF...ELSE IF labels and the ability to change the order of the conditions) my first thought would be that the conditions evaluate in order from top to bottom.
However, in the documentation for this node it states:

"Conditions are evaluated in bulk, without regard to the order in which you list them." 
 "Do not stack gateway conditions such that the first condition must execute before the second condition is evaluated. To avoid this, write the primary condition into the secondary one to ensure that the desired logic takes precedence."

But then in other places the same page states:

"Each outgoing path is assigned a condition. The conditions are evaluated according to their top-to-bottom ranking. As soon as a True condition is discovered, the workflow takes the associated path."  
"If you have more than one condition, reorder them so that they are evaluated in proper sequence. The first condition listed is the first to be evaluated."

The actual behavior of the XOR node indicates that the order of the conditions does not matter, all are evaluated simultaneously. I hope that Appian changes the behavior of the node to execute conditions in order as this would be much more useful.
If I have misunderstood anything in the documentation, please feel free to correct me, because as of now I don't really see any value to an XOR node when compared to an OR node.

jackf0001 · Accepted Answer

I ran into an issue with this today, but I believe I have figured out why. My problem was that condition 3 was throwing an error, but (in my mind) condition 3 should never have been evaluated because condition 2 was true (which prevents that error). Basically, I was expecting it to operate like an a!match statement. However, we're now thinking the node evaluates all conditions at the same time, and then takes the path of the first (topmost) true condition. This would make much more sense and explain why both "conditions aren't evaluated in order" and "condition order does matter" are present in the documentation. I think the documentation could make this a lot clearer though.

james.lepone · Answer

The important thing to remember is that all the conditions will be evaluated (as opposed to one at a time until reaching a true condition). What that means is if there are two conditions, one which checks if a list is null, and the next that tries to remove a value of the list, an error will be thrown, since the second condition does not have a null check, even though the first path should be taken. Screenshots attached.

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