I agree with what's been said so far. The day I become fearless is the day I need to find a new career. I think the challenge and the skill is learning how to control that fear, how to manage it, and how to apply it in a positive sense.
I try to be pragmatic wherever possible. In theory, I know I can RSI this inhalation injury but the pucker factor is huge because I am aware of the risks, complications and outcomes. The stark reality is it needs to be done to do my part to minimize morbidity and mortality. If I am fearless, I take too many risks (short cuts, no back-up plan, etc) and have a higher liklihood of being unsuccessful. If I am fearful, I fail to act and respond accordingly.
I think by not being fearful nor fearless, I can be aware of both extremes and it helps to keep me honest and patient focused. Everything I do is risk vs benefit based. In my example, failure to do anything obviously results in a poor outcome. If I am fearless, maybe I am lucky and I am successful with a positive outcome. The reality is, you're playing with fire and you will eventually be burned. It's not a matter of IF, rather, WHEN.
The other factor is if you are fearless, you are the 'I' of the 'team' (there is no 'I' in team) and you are probably a burden to the rest of your crew.