Sorry to disagree, but in my experience P&B can and do cause leaky gut (and possibly other intestinal problems). When they rip the candida off your gut wall, this leaves behind holes/damage otherwise known as leaky guy. It is really a sledgehammer approach.
I think they could/should be used, but with caution. They are certainly no magic-bullet.
I used P&B shakes for 5 months to fight my candida. Candida is still there, but I lost 2 stone of muscle.