a crowrd traffic . not very ideal for time attack so decide to pratice with left brake. after 2-3 lap of pratice . i get most of it right. without even using 2 gear. i am only .3 sec slower from my fastest lap time 
with left feet brake you can have less impact of weight tranafer so catherham wont shift too much weight off rear. make car more plant then 
right feet brake. but still left brake is a bit challenage to dial in exact brake pressure