I've read easily 30 books in this subject area where the writers are consistently more accomplished and broadly/deeply knowledgeable on relevant subjects, terrain, and sailing than the armchair critics. Enterline's a mathematician/computer scientist and approaches the subject with far more rigor, skepticism, and fact-checking than a professional historian who generally has little or no training in the sciences and considers only convenient books by peers the source of reliable information. Enterline writes with great lucidity and doesn't pad his paragraphs but fully supports his conclusions with original sources. His books are a pleasure to read, relentlessly logical, and full of surprising and fascinating insights in the actual discovery and exploration of Northern North America.