slvoid,
You cannot put the safety "back on" on a Glock as there is no external safety like those on other pistols, the insternal safety is re-activated when you remove your finger from the trigger. But we appreciate your attempt at gun safety. :-)
I found my HRM (which just broke after about 3 weeks of use) to be a great training tool. My inclination was to hammer both to and from work regardless of how I felt or what my body needed. I would find myself burned out by the end of the week and also realized that I wasn't spending my riding time as efficiently as I should have in order to burn fat. I think that if you were to concentrate on staying in your cardio zone for most of your ride that you'd feel much better. It is difficult to resist the urge to hammer (sometimes you have no choice) but, in the long run, I think you'll feel better for it.