No. This has been discussed in detail on the mailing lists already. 
Please search the archives if you are interested in this discussion.

Turba already supports multiple email addresses, and you can even add 
more. It up to how you configure it.

Turba already has duplicate searching and merging.
That's a valid point, please create a new enhancement request in the 
proper queue (Turba), if one doesn't exist already.

Bugs or features?  Well, I consider annoying features as bugs.  But at 
least the software works for me as I somewhat expect.  Please fix 
these weirdnesses:

1.  checkboxes on mail - when I check a bunch of boxes, then 
accidentally click outside the check box of an item, Horde unchecks 
everything I had checked.  This is nuts because I have to go back and 
recheck everything.  Fix this by requiring Esc to uncheck, and 
providing undo/redo for check operations.  Accidentally clicking 
outside a checkbox must not uncheck everything.  If nothing more, 
prompt the user as to whether to uncheck everything.  Yes, I realize I 
can simply hold down the shift or Ctrl key and click to select.  I had 
to mess with it a while before I figured that out.

2.  Import from Gmail address books properly.  I save Gmail address 
book to a vcf, then import into Horde.  Some Gmail contacts have 
multiple email addresses.  Horde allows only one email address, but 
multiple phone numbers.  To accommodate this weirdness, Horde creates 
additional entries for a given contact, with a different email for 
each, but Horde does not show the differences between the contacts.   
This creates a confusing address book glut of contacts. This fact 
worsens the problem:  Google has promoted its Hangouts to all new 
Android 4.4+ phones, starting with Nexus phones, and any user with a 
gmail account has automatic synchronization of the phone contact list 
with the gmail contact list.  It would be wonderful if Horde allowed 
one to keep its address book synced with gmail, outlook / hotmail / 
Thunderbird contact lists.   At the very least, add more email address 
fields to the horde contact list so that import from gmail does not 
create additional name entries, and let users specify the "Default" 
email address and phone number.  Furthermore, provide a way for users 
to show email addresses AND phone numbers on the screen that displays 
contacts in the address book.  That screen could show whether contacts 
are duplicates of each other, or MOSTly duplicates.

3.  We NEED features to help us clean up address books that have 
duplicate entries or mostly-duplicate entries.  Most users do not need 
or want duplicate entries.  I have a ton of email-address-only 
contacts, where I don't even know the name.  Gmail and Thunderbird 
seem to stash these in the contact list.  Many of these also exist in 
entries with names.  I want Horde to offer a feature that scans the 
address book and merges all email addresses having no name with 
contacts having names and identical email addresses.  I also want it 
to merge all contact names with multiple phone numbers or multiple 
email addresses.  THIS is the most messed up area of all email/webmail 
clients.  Horde can show some leadership by fixing the problem better 
than any other product does.

4.  After searching in the address book, or editing a record, we have 
no way to return to the previous screen.  Alt left arrow produces a 
message about form submission.  This is frustrating and annoying.   
Provide a way to return to the previous screen.