I don't see why you can't restore.
Ideal is to do a walk-thru and test what a restore is and does and such - when you have time and things are working.
When I restore, I format and then restore. Or you can erase.
with enough drives, there is almost no need unless there may be structural errors, or you want to move the system to a new larger or faster drive.
HELP menu in programs like Disk Utility plus it is quite easy
I am not audio or protools, more system maintenance type, and I have no idea why or what is different. But I do know that if I have a system that works, I would make a copy (clone) of it and keep it safe (and off line).
Having spare drives handy is a must, along with SuperDuper and Disk Warrior.
Clone with SuperDuper doesn't copy temp files, log and caches, which is great, those can be problematic and just take up space, and are best recreated fresh.
I would never say a drive is working 100% okay without also using Disk Warrior, maybe even TechTool Pro 5.
Just DO NOT rely on only Apple First Aid to tell you or keep a drive in tip top shape and working order - it doesn't and won't.
A newly formatted drive insures a number of things. You can also write zeros over the drive. A drive used by 10.6.3+ really should be formatted by Snow Leopard, especially system drives. Yes you can just install over Leopard and update, but it really isn't the same.
I buy a lot of drives, but I trust all 4 systems I have to WD VelociRaptors for the most part, built like SCSI drives use to with good low seeks and latency, and run cold but fast.
Also nice to have 4 systems so one can be used for testing or something or a job that takes a lot of time and leave me free.
I'd take your problem system, use SuperDuper (free for full clone, inexpensive $29 for "Smart Update" feature) and clone it to a newly initialized drive; plus run Disk Warrior 4.2 against it first. Then run from that.
I've had three WD drives out of 30 fail, all WD Caviar, two were "Black" series, one was repaired and works fine now thanks to WD's Windows utility. But I won't use Caviar drives except for storage and triple backups now.
I was worried that going back and forth with different versions of AVID apps might handle data files differently, like how Microsoft changes Excel/Word .docx files.
About CCC and other issues:
http://macperformanceguide.com
How to clone with CCC
http://macperformanceguide.com/Mac-HowToClone.html
Even for non-RAID (but definitely for use with RAID) nothing beats SoftRAID for reliable and easy to setup partitions.
http://macperformanceguide.com/Mac-DiglloydHardware.html
http://macperformanceguide.com/Storage-SoftRAID.html