LAST EDITED ON Mar-24-16 AT 09:04AM (MST)[p]LAST EDITED ON Mar-24-16 AT 08:59?AM (MST)
Hey Pete. I'm one of the creators of toprut.com.
You are correct in that the Simple Draw Odds column on the overall summary page does in fact show what you are describing. However if you click through to the unit detail, the information in the Random Draw Odds chart is in fact calculated in the "correct" manner in which you describe.
We chose to include the Simple Odds in the summary chart just as an indicator of relative difficulty at a glance (we will footnote that better). It's not perfect, and we will continue to make improvements over time. For now our focus is to stay heads down compiling data but we've got some cool things in the works.