Revert "[#2475] Tweaks to new session on-demand docs"

This reverts commit 7f288dcc476b640cd0c0a81c37a9b0721353be2d.

Reverted because the code change was reverted.
Revert "Merge pull request #2475 from drak/session_demand"

This reverts commit bd3e58e342632671e7fd31369c75ed49bb7ce053, reversing
changes made to 73e5095f59fb6c1b246b4a9688159ade18b74a86.

Reverted because the code change was reverted