Talesin, I don't remember any blood stuff about Masons. As kids we used to take secret blood oaths in the neighborhood. It was common to slice out little fingers and become blood brothers. That is not gross or unusual.
Girl Scouts don't have death dealing secrets(blood oaths), no of course not because of course, you'd know all about them.
Perception is just that, perception. What an embarrassment for a big deal big Mason guy to be caught doing some silly- ass ritual which he'd never do in public. He'd say "HEY YOU"
The "secret" of the RCC rite of transubstantiation is supposed to be secret on pain of death, but you can read about it in the Catholic encyclopedia.
The whole magic thing is best considered in the movie Peggy Sue Got Married, where her (Peggy's) grandfather's lodge sends her forward in time. Whatever. You'll see bogey men around every shadowy corner if you aren't careful.
The Masons are a club. One of the few clubs guys who don't attend Yale can get into w/ the guys who do. It's some kind of pride of belonging.
And if JT does join, the dubs will think he's some kinda Grand Leapin' Lizard. They will be as paranoid around him, as you are with the Mystical Mason Magicians.