Hi Ray
Yes, the system is about as clear as mud.
I don't think that any individuals are responsible for the situation. Just seems to be the system in general.
Having spent hours & hours reading both the DVLA & VOSA websites, information into the full IVA process is non existent.
Even at local level. Speak to VOSA in person, different staff will give you conflicting advice.
The same is true if you speak to staff at your local DVLA office.