I spoke with a customer regarding an external Mac hard drive that he was trying to recover his data from. The external hard drive was starting to fail – mounting sometimes and other times not. This recent attempt he couldn’t get it to mount to the desktop. He had previously tried copying data from it but in the middle of the process the hard drive was unmounted and the copying was stopped. He then found Prosoft Engineering’s Data Rescue 3 Mac Data Recovery Software. He downloaded the free trial and started to run a “Deep Scan”.
A Deep Scan is a comprehensive data recovery scan method that provides the most results possible. He thought he was doing great untill he got a read error, which said if he continued any further there could be further damage to the drive and Data Rescue 3 suggested to create a clone. He wanted to know how a clone could help him recover the data. I explained to him the clone of this bad drive to a good drive would copy the data from the bad drive and plant it on a good drive that can then be scanned to retrieve the data.
I helped him setup a reverse clone to run and then told him about the 2nd step, which is running a Deep Scan on the cloned drive to recover the data. I explained to him the clone process is easier on a failing hard drive and always a good choice on a drive that has physical problems. So, cloning a hard drive definitely does help data recovery.
There is another helpful article of mine regarding data recovery using Recuva, you can also read this.