I did a search for this because I thought it would have been brought up many times - but I couldn't find anything. I don't understand the benefit of width not being effected by zoom with the calligraphy tool.
The Inkscape.org tutorial justifies it by saying: "This makes sense, because the natural "unit of measure" in calligraphy is the range of your hand's movement, and it is therefore convenient to have the width of your pen nib in constant ratio to the size of your "drawing board""
I could understand this if the calligraphy tool was only ever used for calligraphy writing. But I would think it's as likely, if not more likely, to be used as a drawing tool. And as a drawing tool this feature is very frustrating. To ensure consistent thickness lines when inking you have to manually calculate the width everytime you change zoom. Otherwise you end up with a mixture of very thick and very thin lines.
Perhaps to not upset traditional calligraphy artists, is it possible we could get a checkbox to toggle how the width is effected when zooming? Even if the feature simply adjusted the value in width field as you zoomed in and out.