Correct me if Im wrong but and IRI is anyone that has passed the NO IF upgrade course of instruction - and also has an IR. If you don't have a valid IR you can't teach IR ratings only IMC, but if you have an IR you can do both. The core course is the same regardless. However, to teach approved IR, you must be further trained and tested on standardisation by the CAAFU department. In the old days, any IMC instructor if they had an IR could teach non-approved IR. Just there is not a non-approved IR available now.
As for not teaching students the LARS service. Shocking. This forms part of the sylabus. Either as a ground brief, home reading, flight example. Plus it is used as a basis for some of the questions in the written exam. Did this topic starter do his IMC in the states? (sorry can't be arsed to flick down the thread!) I note you live perhaps both sides of the pond?