'Terrain Decoration' video setting does not work as intended [full explanation]

The result of each 'terrain decoration' setting varies depending on what setting you launched the game with. So there are actually 16 different settings, not 4. E.g starting the game with 'terrain decoration' set to 'low' then setting it to 'high' will look completely different to starting with 'terrain decoration' on 'ultra' then setting it to 'high'. Here are my screenshots that prove this: 

Low: 
started on low: https://www.dropbox.com/s/aragsdy50gy286o/L_TD-low.jpg [dropbox.com] 
started on medium: https://www.dropbox.com/s/9a4y58mliqixx6n/M_TD-low.jpg [dropbox.com] 
started on high: https://www.dropbox.com/s/9pxh79nmayluc0m/H_TD-low.jpg [dropbox.com] 
started on ultra: https://www.dropbox.com/s/53qdnh3oy1qxx01/U_TD-low.jpg [dropbox.com] 

Medium: 
started on low: https://www.dropbox.com/s/dztrw6kzz6nnyhm/L_TD-med.jpg [dropbox.com] 
started on medium: https://www.dropbox.com/s/ay2ow8vdd4ubioz/M_TD-med.jpg [dropbox.com] 
started on high: https://www.dropbox.com/s/y7nt3f2cdwg3aq5/H_TD-med.jpg [dropbox.com] 
started on ultra: https://www.dropbox.com/s/3qzinc8lgd7o02e/U_TD-med.jpg [dropbox.com] 

High: 
started on low: https://www.dropbox.com/s/50isj0g7mz90mnm/L_TD-high.jpg [dropbox.com] 
started on medium: https://www.dropbox.com/s/jzrkscz5qk5e313/M_TD-high.jpg [dropbox.com] 
started on high: https://www.dropbox.com/s/x4yy41bcaqjjh7a/H_TD-high.jpg [dropbox.com] 
started on ultra: https://www.dropbox.com/s/uk0ia4ky551b6yk/U_TD-high.jpg [dropbox.com] 

Ultra: 
started on low: https://www.dropbox.com/s/wafsnh3shq9vl9f/L_TD-ultra.jpg [dropbox.com] 
started on medium: https://www.dropbox.com/s/cjm9m4sn3ytgl1d/M_TD-ultra.jpg [dropbox.com] 
started on high: https://www.dropbox.com/s/i62b590h277jvm5/H_TD-ultra.jpg [dropbox.com] 
started on ultra: https://www.dropbox.com/s/swaplp6pu5j2t7z/U_TD-ultra.jpg [dropbox.com] 

It gets worse, the following applies to each of the 4 settings once you are in the game: 

low = high 
medium = ultra 
high = medium 
ultra = low 

So if you are currently set to 'Ultra' and just leave it, that will give you roughly the equivalent of somewhere between medium and high.

### SOLUTION (if you want true ultra) ### 

1) Ensure 'terrain decoration' is set to 'ultra' before joining a game or starting a new map. 
2) Join a game or start new map and set 'terrain decoration' to 'medium'. 
3) Redeploy. You will now have real ultra setting. 

NOTE: This is not permanent! You have to do this every time you join a game, and every time you start a new match!

Tests were done under Win 8.1 on a 4930k+780ti.

Apparently this bug has been around since the game was launched! Why hasn't it been fixed yet!?