A few observations,
1) Linear DNG output from DXO Optics Pro is not new of 9.5. It has been there a long time ago, at least from version 6.
2) The new thing is the LR plugin that allows to export a raw file from LR to DXO (LR usually exports rendered files to external editors). In the past, DXO OP had the ability to read from LR catalogues, so you could use LR as DAM, select the images, and then open the catalogue from DXO and select a specific collection. This worked with DXO 6 and probably DXO 7 with LR up to version 3. This new plugin is even better than the old way to read LR catalogues.
3)If you convert your raw files to DNG without keeping the original raw, then you cannot use this plugin, since DXO does not accept DNG as input (except those created directly in camera, as few models do)
4)The output DNG from DXO is a linear DNG meaning that it has been demosaiced and interpolated, because this is a necessary step before applying optical corrections.
5) The output DNG is less processed than a TIFF. It has not been encoded to a color space (so you avoid the limitation of Adobe RGB if you output TIFF). Additionally you can apply your preferred DNG profile and you can even create a DNG profile with the Xrite tool from this linear DNG.
6)When to use this route: If you want the Prime noise reduction and/or DXO optical corrections, which for some camera / lenses combinations are superior to Adobe's in my own experience, especially the "lens softness".
7)Note if you go this route: Apply white balance in DXO if you have blown out highlight. The explanation for this is long and has been posted in this site a while ago. If you do not do this and wait until returning to LR to apply white balance, you might end with color casts in those highlights.
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