I kind of understand what you were trying to say, and first just want to say in regards to others that have commented that I CAN NOT STAND when someone tries to pull rank (however I may have misinterpreted the authors comment and what they meant was an individual who has more experience and therefore a less ignorant viewpoint). I think you were justified in defending your comment, although maybe should have defined better what you meant by the principles.
There will be students who apply to DO schools for safety, or because the location suits them better than the MD schools they got in to, or because they were offered money. There will be students who apply to DO schools because they are interested in the "Osteopathic Prinicples" (and although one is correct in stating that anyone can use a "holistic approach" in regards to mind, body, soul of the patient, this is NOT the only principle that a true Osteopath would follow). OMM will always in my opinion be the key difference between MD and DO students. Many DOs do not want to hear that you want to be a DO because you want to be a holistic doctor, because ANYONE can be, but they are going to want to hear why you are interested in their school specifically, and OMM. Talk about the rule of the artery, how the body is a unit, the "holistic approach to the body" (structure and function relationship), how the body is self-regulating and self-healing (this is a great topic to discuss when bringing up over prescribing drugs). These are the things that will make you stand out as a DO applicant, not the "I want to treat the patient and not the disease, I want to focus on mind, body, spirit" (which, everyone should, and is no longer just an osteopathic thought, thank god).
And there are plenty of DOs that still use OMM in their specialty (that are NOT just in an OMM specialty), however there are plenty that will never use it. You will decide when you learn it if it is for you. Those that are great at it and believe in it will use it, unless they chose a specialty where it will not apply (i.e. Radiology, although I guess you could make arguments on an interventional radiologist using a couple techniques..but doubt they would). I didn't start to become comfortable with it until the end of my first year.
And when you get to your interviews, just do you. Explain honestly why you want to pursue a DO degree, and don't worry about those that are doing it for what you may consider the wrong reasons. Many people in life will unintentionally offend, and it is good to let them know they did so, but also consider that it may have been unintentional, take a deep breath, and let it go.
Evidence based medicine shows a lack of negativity helps you live longer.
Hope I was a little helpful, and if not I only wasted my time I guess!