Bob's World said:
Both are good tools, both can be abused, neither stands alone; and both can be "over-doctrinized."
Design helps you get the problem (more) right by supporting the establishment of a hypothesis (X is the problem) and from which a theory (e.g. if I take the following actions (Y) they will/may result in a range of possible outcomes (Z,Z1, and/or Z2, etc.). You can then explore that range of possible outcomes to develop an operational approach.

The goal is to figure out which conditions associated with the problem must change in order to bring about a desired or tolerable outcome (possibly for more participants than just your team), then figure out the actions or tasks which will bring about those conditions.

During the actual execution design is handy to look at how things are progressing, and/or how the introduction of new factors affect the desired outcome. This may cause you to "reframe" your problem.

It may be useful here to have a way to measure those changes in conditions to which you have designated tasks to see if you are doing the right things, and to measure the performance of those tasks to see if you are doing the right things well. This however is not part of design as I understand it, but is still prudent and useful as there are a number of things that may be changing or resisting changes.


Enter MDMP -

Sooner or later once a decision has been made to do something, physics become an issue. Analytic processes such as MDMP get to the nuts and bolts (details) of moving stuff around, synchronizing time tables, etc. MDMP is therefore a useful tool to get after the details and the mechanics - there is not much theory here, but there is allot of action

As Ken points out -
trying to break things down to the lowest common denominator is not a good plan for either understanding combat skills or teaching how to think versus what to think.
which I think leads to COL Jone's point about part of what leads to "over-doses of doctrine".

Both processes should remain descriptive as much as possible to allow for flexibility in execution. To chew on something till its bland enough for everyone may lead to something less than useful.

Best, Rob