Viewing all steps available without pro membership Answered
1. Visit any instructable
2. Click "view all steps on one page"
3. The page will show you all steps on one page even if you're not logged or you're logged but don't have pro account.
Links to screenshots (look at the addressbar, link of hovered step on the bottom and size of page's scrollbar):
Tested on: Firefox 14.0 (with adblock turned off), Chrome 21.0.1171.0 dev-m (with adblock turned on)
Clicking on "save as pdf" button opens window with information:
"All Steps Viewing
View all steps of an Instructable on the same page when you're a Pro Member."
so everything looks fine with "before-PDF authorization"