Perhaps, but frankly synching your device with your desktop's Outlook inbox
is kind of a quaint holdover from the days when PDAs had no built-in
connectivity (no WiFi, BT, cellular, etc.) You synched in the morning to
get your emails on the device, composed replies offline, and then resynched
later to send those replies through your desktop and download newer email to
the device. Activesync (in the "sync-email-with-desktop-Outlook" mode) has
no way to send your email from the device- you have to resync so it can be
sent from the Outbox on your desktop.
In today's connected world, Activesync's email sync is generally used to
sync with an Exchange server for up-to-date email rather than the desktop.
If you want to sync your entire folder hierarchy: inbox, sent items,
subfolders, etc., you could use IMAP (or POP, but IMAP is far better suited
to sharing an email account between multiple devices) and setup the same
account on the device, rather than sync with Outlook on the PC, giving you
the option to retrieve fresh email on the go, as well as send email directly
from the device.