yeah it's important to remember that riding during a triathlon is chock full of restrictions, the most prominent of which is NO DRAFTING and a 15 sec maximum allowance for passing. for this reason, factors such as the degree to which you can make your body (and bike! hence triathlon-specific bikes...) more aerodynamic are important.
when it comes to solo training rides or group rides, i would never recommend aerobars. i would caution against them in particular when it comes to urban settings or busy suburban settings, as a tremendous amount of control is sacrificed for aerodynamism in an inappropriate context.