Must use equal parts of gin and vermouth in this outstanding cocktail. Upping the Benedictine slightly is also a good idea. I used Himbrini Icelandic Old Tom which is a bit different than my usual Haymans. I now prefer the Himbrini and the complexity it brings. Did not use the saline solution but will try it next time. A great cocktail!
In my haste to imbibe I used Haymans Old Tom gin rather than a London dry. I think it made for a smoother version. Also agree that a bit of chilled water helps bring out the cocktail.
Made from the recipe in your book and then noticed the changes here online: you have decreased the gin and vermouth and increased slightly the other ingredients. I will try again with this online version, and interested in the salt added. Also, nick & nora glass change is a good idea. The book version is a bit boozy.