I personally hate the method of blocking off tasks in a calendar because it is: a) Not agile (can't adjust your priorities quickly). So you get sick one day then you have to adjust your entire calendar for the next month? b) Very cumbersome and totally not suited to the concept of lists of things to do.
To do lists are perfect for storing information about what you might do in the future. You can create various lists to hold information, so that you don't have to constantly try and remember it. Then each day you prioritize and figure out which tasks you are actually going to work on. The point of the to do list is not to create a list of tasks that you are absolutely going to work on necessarily. Instead it's a way to store information and then jog your memory when you decide what you are going to prioritize and actually work on.
So overall I think the idea of forcing yourself to plan ahead of time exactly what you are going to do several days in advance is a horrible idea and very ineffective. What if something more important comes up on the day? You get a call from Techcrunch that they would like to feature your app. Sorry Techcrunch you're not on my calendar.