With the release of psxt001z 0.20 beta 12, which is able to scan both discs and images for LibCrypt protection, it has now become an obligatory part of PSX disc dumping process. You can read more about LibCrypt protection and its detection here.
As you may have noticed, site's domain name and hosting have been changed. The new hosting should be much faster then previous, and as for domain name, old one will be back in a couple of days.