Here are some rulings found on the old forum. I hope I have provided enough context, and I'll dig for more rulings as time passes on.
Casey was wrong.
The relevant FAQ entry for this kind of situation is: (any effect that grants or removes a keyword is a lasting effect)
(v.1) Multiple Lasting Effects
Even if not triggered at the same time, multiple lasting effects may affect the same card at the same time. The order in which the lasting effects take place is irrelevant – the net sum result of all lasting effects is applied to the card.
<snip>
Lasting effects that affect other character attributes work in the same fashion.
If you have "Fast" from 3 sources, you still round down to "one" Fast, but if another effect enters the equation, you would recalculate from scratch, and then round to one or 0.
By toughness being cumulative, you simply never round off to one or zero. With the other keywords you do, but when the equation changes you don’t start from the rounded value, you reconsider all lasting effects that are being applied to the card.
Brazier of Nodens Vertiginous Visions
Forced Response: