As long as bishops can make the call and never be questioned about their decisions, it will never change.
http://www.canonlaw.info/canonlaw915.htm
United States Conference of Catholic Bishops, Catholics in Political Life, Origins 34/7 (1 July 2004) 97, 99, on-line here.
“Given the wide range of circumstances involved in arriving at a prudential judgment on a matter of this seriousness, we recognize that such decisions rest with the individual bishop in accord with the established canonical and pastoral principles. Bishops can legitimately make different judgments on the most prudent course of pastoral action”.
Absolutely every element of that statement is a LIE.
Circumstances are IRRELEVANT, because giving Communion to pro-aborts is ALWAYS gravely sinful. "Prudence" is never involved when it's a question of committing a mortal sin. The decision does NOT rest with the bishop, because NO ONE has the authority to command anyone to commit a mortal sin. Bishops CANNOT make different decisions because NO bishop has the authority to negate the mandate of Canon 915. Cf. http://tinyurl.com/pont915 See section #4.