Im adding a 13mm this season...however,the biggest factor for me for flat cornering was LOWERING my fox floats,down to where the A arms are slightly LOWER then horizontal.....I ride GROOMED trails,so I have no probs running mine low...the lower center of gravity makes a huge difference,even with my transfer rod set loose,it stays flat....
not quite as low as my radaring pic in avatar...but lower then most run theres....
Ill post more on my findings with the 13mm bar this winter..hoping it is even flatter!
Dan