Map Takeoff Blocked-Off Spot

I found this while playing takeoff_inf (if there is a difference in the maps)
The Steps on How to Get There (view the album images from left to right)
1. When you spawn, look left.
2. Enter the grey door
3. There should be a one-block-wide window made of glass panes. The space in the images has already been shot out.
4. Stand in the space where the window was. Now you should see some cobblestone walls.
5. Hop onto the cobblestone walls and walk along them until you see a red platform with glass in the middle.
6. Get onto the red area and you're pretty much set.
I don't know if this was intended, but it's pretty OP, and I know from experience.
Album: http://imgur.com/a/cm7FH#0