"off dry"

"Vilco" inquired of the collective wisdom of the group .....

If one means the literal translation, demi-sec would mean "half dry" so the answer would be yes.

However, if one was referring to Champagne, then it takes on quite another meaning: sec indicates a relatively sweet wine, whereas demi-sec is even sweeter.

Et tu, Brut?

When it comes to Champagne, many people say they like dry, but really like a bit of sweetness. This perhaps explains why the real dryness/ sweetness of Champgne, at least that sold in many countries, does not agree very well with the words that describe it. Even Brut can have a touch of sweetness. Champagne tends to be a very acid wine, and a bit of sweetness often can make it seem more balanced and smooth. Only the best Champagne has the balance and lack of bitterness to show well with no added sweetness. A bit of sweetness can hide many sins in Champagne.

Hmmm, you can find plenty of Champagne in the 17-22€ range that is well balanced and does not need much dosage, if any at all. I am not sure what you mean by "bitterness", I have not found that in Champagne.

For cheaper bubbles, it is best to skip the Champagnes that need the sugar to cover faults. At half the price above you can find top Vouvray; it will not match a good Champagne, but it will be better than any sugar-corrected Champagne in the same price range.