Working with the dates and times is a major pain in the ass. It's also a solved problem. Introducing a new system isn't going to help anyone.<p>So now every January 1st is a Monday. So what? Also, why Monday? Make it Sunday so NYE/NYD fall on a weekend. Christians would also be happy about Christmas being on a Sunday. Why put the extra week in December? Who the hell--in the northern hemisphere--wants an extra week at the worst time of the year? At least compromise and stick it in April or October. Or maybe we can trade back and forth between hemispheres.<p>This is just replacing calendar complexity. Instead of some [already written] logic around leap days, we've now got to deal with new logic around a leap week "every five to six years" (and how is that determined?). Any logic dealing with historical dates also has to handle computation between both systems. It's bad enough transitioning between Julian and Gregorian, but we're not still managing mortgages from the Renaissance.