Softy, I had several thoughts and reactions to your post:
First- I think its' very wise that you've stepped back and taken some time to really consider whether you could/should have that beer, you've been considering. I think that with many folks, me included, it's too often an impulse decision, that is rapidly made (and maybe rapidly regretted).
Second- your humility and wisdom to come to this august group and get their collective advice is great. I have read the responses from some folks whom, I have come to really admire, is really wise.
Third- I can relate to your achievements in your physical fitness, based on your sobriety. I too am very active (cyclist) and via my cycling coach and some sophisticated heart rate monitors and wattage-output sensors that I use on my bike while training, I have empirical evidence that I am stronger, and more fit; AF vs. while I was still swallowing poison. And, for me and I suspect for you, the achievement of this enhanced fitness is just one more tangible reason to never swallow a drop of poison again.
Fourth- finally, doesn't all come down to a measure of risk/rewards? Sure, having a beer has some level of reward in it. But, does it even come remotely close to the risks? As I said, this point has been made much more eloquently by others.
Good luck with your decision.
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