Please do this:
(1) Go to tchristy.net.
(2) Enter the term "Sprayer" (without the quotes) into the search filed, upper right.
(3) Click Search.
(4) It produces a page with three items.
(5) Click the middle item (4 1/2 Gallon Back Pack Sprayer).
(6) On the detail page, click the browser back button. You get "Document Expired" in Firefox (not sure in other browsers).
The customer expects the "back" button to go back to the search page.
Of course all this is dynamically generated out of a database. I understand the back button issues.
I know there are messy issues trying to "control" the back button.