Is there any way to more accurately control the proportional edit tool? Each detent on my mouse wheel seems to make the proportional circle jump in large increments - too large for my current project. Also can you use the tool on just selected vertice loops without affecting nearby vertices? 
Alt + the numpad + or - keys changes the size of the tool for me.
Try hiding the verts you don’t want to be effected.
Hide the vertices you don’t want to be affected (h, alt+h to unhide.)
The only thing you can do is turn off PET, Scale the Object larger, do editing with PET, then scale it back (Alt-S, but only if you did Ctrl-A before scaling larger).
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