Why Bismarck was unlikely to slip through the Denmark Strait

Could Bismarck have passed through the Denmark Strait without detection?

Probably not: ice narrowed the passage to well under one hundred nautical miles, two radar-equipped cruisers patrolled it, and the Royal Navy knew it was Germany's favored route.

Ice narrowed the usable passage to well under one hundred nautical miles. Two radar-equipped British cruisers patrolled that constrained channel, leaving little room for Bismarck to pass unseen. Earlier German raiders had already demonstrated that the Denmark Strait was their preferred route into and out of the Atlantic. Bismarck might have improved her chances by turning back after contact, but continuing through the choke point made detection highly likely.