I have never taken an ASA so I don't know what they say navigation is but I have copy and pasted what Bowditch has to say on the topic. The parts you folks are calling not navigation are "Piloting" under types of navigation and the Inland and Harbor/Harbor Approach phases in this text, which is probably the most respected of the American texts.
INTRODUCTION TO MARINE NAVIGATION
DEFINITIONS
100. The Art And Science Of Navigation[edit]
Marine navigation blends both science and art. A good navigator constantly thinks strategically, operationally, and tactically. He plans each voyage carefully. As it proceeds, he gathers navigational information from a variety of sources, evaluates this information, and determines his ship's position. He then compares that position with his voyage plan, his operational commitments, and his predetermined "dead reckoning" position. A good navigator anticipates dangerous situations well before they arise, and always stays "ahead of the vessel." He is ready for navigational emergencies at any time. He is increasingly a manager of a variety of resources--electronic, mechanical, and human. Navigation methods and techniques vary with the type of vessel, the conditions, and the navigator's experience. The navigator uses the methods and techniques best suited to the vessel, its equipment, and conditions at hand.
Some important elements of successful navigation cannot be acquired from any book or instructor. The science of navigation can be taught, but the art of navigation must be developed from experience.
101. Types of Navigation[edit]
Methods of navigation have changed throughout history. New methods often enhance the mariner's ability to complete his voyage safely and expeditiously, and make his job easier. One of the most important judgments the navigator must make involves choosing the best methods to use. Each method or type has advantages and disadvantages, while none is effective in all situations. Commonly recognized types of navigation are listed below.
Dead reckoning (DR) determines position by advancing a known position for courses and distances. A position so determined is called a dead reckoning (DR) position. It is generally accepted that only course and speed determine the DR position. Correcting the DR position for leeway, current effects, and steering error result in an estimated position (EP).
Piloting involves navigating in restricted waters with frequent or constant determination of position relative to nearby geographic and hydrographic features.
Celestial navigation involves reducing celestial measurements taken with a sextant to lines of position using calculators or computer programs, or by hand with almanacs and tables or using spherical trigonometry.
Radio navigation uses radio waves to determine position through a variety of electronic devices.
Radar navigation uses radar to determine the distance from or bearing of objects whose position is known. This process is separate from radar's use in collision avoidance.
Satellite navigation uses radio signals from satellites for determining position.
Electronic systems and integrated bridge concepts are driving navigation system planning. Integrated systems take inputs from various ship sensors, electronically and automatically chart the position, and provide control signals required to maintain a vessel on a preset course. The navigator becomes a system manager, choosing system presets, interpreting system output, and monitoring vessel response.
In practice, a navigator synthesizes different methodologies into a single integrated system. He should never feel comfortable utilizing only one method when others are also available. Each method has advantages and disadvantages. The navigator must choose methods appropriate to each situation, and never rely completely on only one system.
With the advent of automated position fixing and electronic charts, modern navigation is almost completely an electronic process. The mariner is constantly tempted to rely solely on electronic systems. But electronic navigation systems are always subject to failure, and the professional mariner must never forget that the safety of his ship and crew may depend on skills that differ little from those practiced generations ago. Proficiency in conventional piloting and celestial navigation remains essential.
102. Phases of Navigation[edit]
Four distinct phases define the navigation process. The mariner should choose the system mix that meets the accuracy requirements of each phase.
Inland Waterway Phase: Piloting in narrow canals, channels, rivers, and estuaries.
Harbor/Harbor Approach Phase: Navigating to a harbor entrance through bays and sounds, and negotiating harbor approach channels.
Coastal Phase: Navigating within 50 miles of the coast or inshore of the 200 meter depth contour.
Ocean Phase: Navigating outside the coastal area in the open sea.