I took my training to be an academic language ther…
I took my training to be an academic language therapist through an Orton-Gillingham school. We were NOT to teach this rule. The purpose of rules is to make spelling easier for students. Something that is reliable only about 50% of the time does not make things easier. O-G teaches very few rules, only 5. With the various vowel-pairs, it's better to study one vowel pair at a time, read a bunch of examples so as to be able to read them in paragraphs.
It's unfortunate that the Lindamood Phoneme Sequencing, LiPS,Progrm teaches this rule. The first 13 chapters of the LiPS Program are wonderful in eliciting and developing auditory discrimination in depth and the alphabetic principle. The otherwise excellent program is just not strong once it transitions into spelling.
The Spelling Blog