I believe when sugar had both the pop and imap for inbound email, the users were able to delete multiple emails at once. Since testing 5.5.1. and 6.0 i've noticed that clients cannot select more than 1 email to delete at a given instance. Considering that some individuals get an abundance of emails daily, it would be very time consuming to delete each email individually.
If anyone has more information regarding this matter, id greatly appreciate it...

Thx
Kyle