I convert all CR2 files to DNG, and delete CR2 (originals) afterwards
Your unlimited trust in the DNG conversion is not justified. Through the conversion you are freezing Adobe's current interpretation of the raw data, which may or may not be ideal, sometimes not even correct.
I am just preparing a small program to correct DNG files, which have been incorrectly converted from 5D2 raw. In this case the correction is possible, but who guarantees, that this is always so?
Btw, I do not believe, that the DNG converted created a linear, demosaiced file "accidentally".
That kind of error is very improbable.