That's also a possibility, but I thought voice recognition may have some trouble with such short commands if they were permanently active, so this would be effectively disabling them until they are more likely to be used
(No idea if this would be an actual issue, but I had a slightly higher rate of failed recognition when using one word/syllable commands)
You might find that tweaking the confidence levels around (higher or lower, depending on preference) , or run through the training windows voice training a couple more time will help with that.
You are correct in that VA can have issues with "single word" commands (or to be more accurate, low syllable count words), but if you keep the commands relatively distinct, a lower confidence level can help with that.
With how Antaniserse has suggested, it get recognised *but nothing happens* unless combat mode is actually enabled.
There can be other problems with VA (ambient noise, echo cancellation) that can screw up the recognition, but they will happen with long or short commands.