My first (and still-current) impression of MAJ Smith's article was that it was an incisive small case study in the methodology of finding and applying a prior relevant and material precedent.

My only critique of the methodology initially employed was the absence of cross-checking the precedent backwards and forwards. MAJ Smith corrected that when he decompressed after returning from Iraq:

from MAJ Smith's article
Since returning from Iraq, I have studied other writers on counterinsurgency, such as Galula, Trinquier, Kilcullen, Kitson, McCuen and Thompson ....
My impression and critique were formed by my own professional experience. The methodology described by MAJ Smith has been employed by UK & US lawyers and judges for the last 700 years since Bracton initiated professional legal literature.

To a lawyer or judge, finding and applying precedents includes substantive precedents (Constitution, statutes, treaties & regulations, and judicial opinions); but also procedural precedents (which teach methods and techniques), often requiring reference to the pleadings and trial transcripts. The latter use, in fact, was Bracton's main focus.

I was therefore surprised that anyone would question the general validity of the methodology which MAJ Smith employed. COL Gentile has well-pleaded the general issue, very succinctly:

from COL Gentile
Of course we should learn from history; I do everyday in my readings and teachings of different historical subjects. But it is different to learn from history, to gain wisdom so to speak, than from reducing history to principles and lessons and applying them in the present and using them also for projection for the future.
Let us be clear that "to learn from history, to gain wisdom so to speak" is not at issue. For example, study resulting in a greater appreciation of legal history (e.g., Plucknett and Maitland), or of history in general (e.g., Will Durant), is admirable.

The issue joined is COL Gentile's argument, in effect, that an invalid methodology consists of "reducing history to principles and lessons and applying them in the present and using them also for projection for the future." Which is exactly what UK & US lawyers and judges do.

If the quote is intended to be a statement of general application, it obviously calls into question the validity of the legal methodology I have briefly described. That would seem to be a heavy brief to carry - in light of 700 years of history.

I assume arguendo that the reference is therefore aimed at invalidating that methodology as applied to finding and applying precedents in the military area from its history. I am hard-pressed to understand why that would be so - and what precedents support that distinction.