Not professionally, although I speak for myself, rather than Mr. Holmes.

[But Douglas does have to admit to his own curiosity, now that Mycroft has dragged him into this a little more deeply.]

I have been a sailor for much of my life. I am no stranger to the seas. But as my colleague mentioned, [cue the slightest sidelong glance at him,] the concept of magic is as fantasy to us both. The longer we remain here-- and I expect it shall be for some time-- the more vital it will be to understand it. A man cannot navigate his ship with no awareness of the winds or tides, after all.