As a newcomer, I would like to thank everybody in this forum for the lively discussion, and especially Matthew for the initial post.
Don't you people think that in order to avoid long debates (which can become sterile depending on who you are talking with), we should simply be a bit more legalistic and stick to the rules? And as far as I know (and I bet that everybody here agrees), here is the 'latest' regulation...:
"We recall that a dress cannot be called decent which is cut deeper than two fingers breadth under the pit of the throat, which does not cover the arms at least to the elbows, and scarcely reaches a bit beyond the knee. Furthermore, dresses of transparent material are improper."
People may argue that this is a 1930 opinion and that fashion changes.
I don't have a problem with those guidelines (though I do sometimes wear shortsleeve t-shirts, whose sleeves don't reach the elbows). I always wear skirts which reach below the knees, usually to the ankles, occasionally mid-calf though.
Trouble is, I could adhere to the rules Pius XI made, and still get kicked out of St Padre Pio's confessional!