Excellent Pen Matt.
Great Blank, Beautifully Turned, and Fitted.
Using BLO, depends on how you apply it, and how much you apply.
If you use several Drops, and apply it on it's own to soak into the Wood, it will darken the wood slightly, it may also enhance the Contrast Colours in the wood.
Then after, you leave it for a considerable time to Dry and Tack off.
You can then apply CA on its own and with several coats, sanding in between and come up with a Colourful wood, and a Good Gloss Finish.
Whereas some Turners, advocate to put one or two small drops of BLO, onto the Pad, then with the two or three Drops of thin CA onto the BLO on the Pad, then apply that to the Wood.
With this the BLO acts as a Lubricant and allows, the CA to flow easily across the Blank.
I usually only use BLO on a wood that is extremely dry, to refresh up the surface, (like you would use a Moisturizer on your skin).
Mainly I use only CA without BLO, for a Fine High Gloss.
I also subscribe to the concept, that it is better, to impart to the bare wood the Highest, Finest Sheen I can through the sequence of abrasives, then through Micro Mesh.
The last couple, really impart a Burnishing Effect, to which the CA gives the Depth to the Finish on the wood.
Congratulations,
Brian