Were "devil" and "damned" really offensive words in Victorian times?

I've been reading Trollope's The Way We Live Now, and have noticed a little stylistic quirk; that the words devil and damned appear blanked out, as d----- and d------. They appear in sentences like...

The d---- you do!

and

It's all d----- nonsense.

The Victorians have an unenviable reputation for prudery, but surely those words can't have been so taboo as to need blanking out, could they? Or is Trollope rendering them this way for comic effect (it certainly makes me smile)?

Yes, the Victorians were that prudish, or at least pretended to be in public.

In Wuthering Heights (published 1847) there's a mention by the "everyman" character Mr. Lockwood of words being blanked out in this way, when he has difficulty sleeping during his stay at Wuthering Heights, and notes Heathcliff's anger:

'And you, you worthless—' he broke out as I entered, turning to his daughter-in-law, and employing an epithet as harmless as duck, or sheep, but generally represented by a dash

(We can only guess what the word might have been, but it must have been obvious to readers then — maybe cow?)

There's also (in my edition) a note in the preface by Charlotte Brontë about the way offensive words were blanked out like this, and how some words were (with much consideration) kept intact rather than being expleted, in order to convey the coarseness of the characters in the novel (devil is used quite liberally). Many Victorians found the novel quite shocking at the time:

A large class of readers, likewise, will suffer greatly at the introduction into the pages of this work of words printed with all their letters, which it has become the custom to represent by the initial and final letter only—a blank line filling the interval. I may as well say at once that, for this circumstance, it is out of my power to apologise; deeming it, myself, a rational plan to write words at full length. The practice of hinting by single letters those expletives with which profane and violent persons are wont to garnish their discourse, strikes me as a proceeding which, however well meant, is weak and futile.

In this 1859 edition of a different Trollope novel, the words devil and damn are not blanked out, even in contexts where it is used as a curse word:

And what the devil is it to you what word I used to her?

Damn him!

The blanking out is found in this 1875 edition of The way we live today, and indeed this modern edition continues the practice. But note that even in the 1875 edition the word devil is also used unblanked as an exclamation (in addition to many literal uses):

What the devil does that matter?

So on this evidence it seems that the words, while frowned on in polite society, were hardly so shocking as to be unprintable; I suspect it is like the situation today where some newspapers will obscure obscenities that other reputable newspapers are happy to print.