I do believe that entering the road backwards helps teachers to make learning meaningful. However, I must aknowledge the fact that there are some difficulties that impeed teacher from writing a 3 pages lesson plan.
First: teachers do not have the time to go through such a time consuming 3 backward step process.
Second: most teachers have to adjust to a previously stated curriculum that usually fits a set of materials.
At some institutions the curriculum is shaped by the materials. Thus, it is difficult for a teacher to go against the tide and start a backward process when they are being forced to teach by coverage.
Therefore, again we are confronted with the problem of having wonderful ideas for teaching and improving the learning process of our students, but that are impossible to apply whatever the obstacles are: lack of resources, lack of time, or lack of freedom. Thus, what is left for teacher to do is to adapt these ideas, on which I think we are becoming real experts.