In the following sentences "so" acts as an intensifier for the subsequent adjectives.
- This car is so expensive. (okay)
- This so expensive car is John's car. (bad)
Can we determine that "so" cannot be used to modify an adjective modifying the subject of a sentence?
- This car is so expensive. (okay)
- I ate a so expensive pizza. (bad)
Can we determine that "so" cannot be used in conjunction with a transitive verb/object noun?
As far as I understand, "so" used as an adjective intensifier must be used with a copula verb and cannot be used to intensify a subject-modifying adjective. Are these the exhaustive rules or are there other outlying examples?