I guess my comment would be in an ideal world copying the sparsebundle.. or even better extracting the backup is far superior and faster than archive.
See Pondini
http://pondini.org/TM/18.html
What happens with an encrypted backup is anybody's guess though.
The sparsebundle can fill the TC but the actual backup inside can be alot smaller..
If you go ahead it must be done over ethernet.. if you only have wireless available forget it.
Only go ahead if the computer is using USB3 or faster drive.
Only go ahead if you have turned off sleep etc.. as you must have the computer running the entire time the sparsebundle is copying or extracting.
The nice thing about archive is, set and forget.. you can turn off your computer and totally ignore things.. even if it takes 48 hours to complete.. you then have a proper disk image of your backup.