Re: gyno without symptoms?
Puffy nipples are not gyno, they're natural in many people (me included), especially when you're warm. They tend to improve with lower body fat ime.
You would truly feel gyno as a tender lump, it's unmistakable when you get it, which is useful because once you have you tend to stop being paranoid about puffy nips and imaginary itches etc.
I was paranoid to some degree myself until I actually experienced gyno, so I understand your concerns. I think nearly all trainers using steroids or pro hormones are in their early days and until they actually experience it. It's easy to allow paranoia to make an itch seem worse, and to make you prod around until you actually make the tenderness yourself.
As said, reducing body fat has had a marked improvement on my puffy nips, they're only really evident when in a hot country now, and due to the lower fat they don't look bad at all as they sit flush to the muscle and hence don't protrude as they used to.