While it is good that you bring to light that the Notes folder does not behave like any other folder, it is pathetic to think, more or less post that this is intended behavior. As a recourse, rather than fixing the issue, which has been known for well over 6 months, you suggest that you remove the DPT AND have users manually apply a Personal Tag to the folder.
There are several issues with this:
1. If you don't have a DPT, then you effectively say "sorry Archiving does not work by default." At this point, decision makers wonder what it is that they spent all of this money on adding Archive mailboxes, when they could have gotten a product that actually archives, such as e-Vault or MailArchiver. "Sorry it does not work and there is no fix" hardly is an answer that can be presented to an oversight committee, unless it is Congress.
2. Placing a dependency on end users to apply policy is not going to work more than 20% of the time. Some will forget, some will ignore and some will howl at the moon, but regardless, it will be ineffective.
3. Since delegations do not allow other users access into their Archive Mailbox in OWA, people such as executives, who have assistants that would deal with items such as this, would not be able to apply the policy.
I am still a bit lost on why it is that RPTs are not allowed to archive, since there is no middle ground between "Everything archives at ### days" and "the user decides to use the personal tag to archive at #### days".
Anyhow, I am hoping that this Notes folder issue gets taken care of soon. Between "unintended" features such as this and bad patches that have mysterious consequences, I have a number of people in important places wondering why it is that we are using Exchange 2010 and what the replacement for it will be, rather than Exchange 201x.