I do not know, but surnames in Ireland I usually see Mc-, such as McGregor, McDermott, McDonald, McKay, McConnell, McMahon, McGuinness, etc. whilst I see Mac- usually in Scotland such as MacEwan, MacLeod, etc. But this is another topic.
"Uncommon Early Moves", the last chapter, starts on p. 413 and the Index of Variations of Variations on p. 429, so it seems as if most coverage is on main lines, which si good.
In the excerpt, on p. 8 last sentence first paragraph, what does it mean new line in the 4. e5 variation?