unexpected (but useful) inbound rule behavior

While experimenting with “on receive” rules, I stumbled upon the following behavior, which happens to be just what I was looking for. What worries me a bit, however, is that I don’t know that it’s been intended to work that way, and therefore might be changed/dropped in some future version. Any further explanation/insight much appreciated.

I am running v7.2.35128 set up with a single EWS account, let’s call it ‘ews-acct’. I set up two “on receive” rules (in that order, from top to bottom in the rules dialog).

(1) after message has been
move to
and make a copy to

(2) after message has been
mark as read

With these two rules in effect, each incoming message is saved to both:
- the folder, marked as unread;
- the remote folder, marked as read.

Again, this is just what I wanted to make happen. But I don’t quite follow how rule (2) works. If I leave it out, then the message is marked as unread in both folders. If I move “mark as read” into rule (1), instead, then the message is marked as read in both folders. It looks like having the “mark as read” step into a separate rule changes what it applies to, though I wish this was actually documented somewhere.

Unfortunately there is no documentation, so trial and error seems to be the only way to learn.

This is the outcome I would expect if either of the Rules are applied to ews account only.