Hi again, scruffdog,
Actually, when you mention the extra saliva, it brings back some experiences I had during recovery. I believe the additional saliva is caused by esophageal spasms, which trigger the saliva as an attempt to soothe the esophagus.
At 5 weeks, you're in the very early stages of recovery, and bending can be very irritating and straining to your newly created wrap.
Think about it...your stomach has been through a lot. It has had stitches undone, and been pulled, wrapped, and stitched again! It's totally normal for it to complain loudly!
Try to relax into your recovery, and don't worry. It's understandable to be on edge...I thing everyone recovering from a Nissen worries about every twinge and especially "reflux" sensations.
Try to be patient! I know it's hard.