CoastalDriver, could you be so kind and elaborate how IAS should be a valid reference value after TOD, determining the rate of descent to stay on a 3 degree path down to maybe 3000ft, until catching the glideslope there?

I am aware that, to prevent falling out of the sky, you better watch your IAS on final approach. But that has nothing to do with maintaining a proper descent angle those roughly 30.000ft before you can catch the ILS and even thereafter.
I can't, from a scientific viewpoint, follow you and the formulas given when it comes to the descent path and maintaining it.

I've actually showed that your IAS/2 = ROD formula leads to a huge offset with doing the maths for you. So the guys using it will end up way too high when starting at TOD down to their destination. How come? The maths are rock solid, so maybe something else is mixed up here.
Expect me to listen closely.  :)