I wish I had a dollar for every opinion posted on the internet as gospel for dry aging as well as trimming – I would be a rich man!
Trimming boils down to your personal tastes. To me I will carefully only remove the very hard top most of the aged meat. When that meat is grilled then “to me at least” it is so wonderfully tasty! That hard outermost turns mellow! But again – it is personal taste. My wife has not yet developed the acquired taste of that treat, so after grilling she will cut off that delightful area and give it to me! Obviously when we have company that’s another story so I will trim her’s and any one else’s steak before grilling.
Now as for the effect on dry aged steaks using sous vide that bark also mellows, but unless you are like me the appearance of sous vide steaks is not all that appealing! What I do is then sear them quickly at high heat to achieve the mallard look.
Good luck and report back to us with your opinion of your results!