thanks. at the risk of being a pain in the neck, and with great respect, i suggest that your solution is poor. Your solution results in a live controller being left laying about waiting to be used .even just picking it up can result in a bump of the controls. sure you could perform the unlock/lock every time you pick it up or put it down, but mortals just do not do that . the alternate suggestion i mentioned is foolproof. i soon becomes natural and cannot be forgotten. as illustration this is why all new saws by law require a dual action trigger (as one example).
Sorry to debate you on this, I will not mention it again.