The British aren't all that good at being perfervid.
In fact, in Britain to be perfervid will probably be seen as embarrassing, or even bad form.
To be perfervid is practically a sign of unreliability or even madness.
The thing is that we tend to be a rather laid-back lot in England, and perfervid describes someone who's extremely enthusiastic or zealous. It describes someone who has a passion for some cause: whereas in England we most admire a person who casts a cool eye over a situation and then makes a joke about it.
It's very hard to be both perfervid and funny; and round here funny wins every time.
In Italy, I understand, being passionate is perfectly acceptable. In Eastern Europe to be zealous seems to excite high admiration.
Here, though, if you work eighty hours a week then I'm afraid the thing to do is treat the activity as a mild inconvenience.
Still, who really wants passion?
Thing To Pretend Not To Be Today: perfervid. This word comes from the Latin per- which makes words more intense, and fervidus, which means fervid, which itself means intensely enthusiastic and passionate.