(b) Because usually the enemy's fleet opens with an attempt to control the common communications.
(c) Because usually the functions of the fleet are so complex (i.e., the calls upon it so numerous) that it will seek to strike a blow which solve all the difficulties; e.g., Sir Palmes Fairborne's solution of the problem in 1703 (England in the Mediterranean, Vol. II., p. 234).
Also it must be remembered that nine times out of ten the most effective way of "seeking out the enemy's fleet" (i.e., forcing an action on him) is to seize a position which controls communications vital to his plan of campaign.
This was what happened in 1704. Rooke was unable to seek out the Toulon fleet, but by seizing Gibraltar he made it come to him (not intentionally, but by the operation of inevitable strategical law).
Compare Togo's strategy and that of the Americans in 1898.
Practically all great Naval actions have been brought about in this way, that is they have been the outcome on an effort to clear essential communications from the enemy's fleet, e.g., Gravelines, La Hogue, Quiberon, Trafalgar, Tsushima.
Similarly the great actions of the old Dutch wars were brought about because our geographical position placed us astride the Dutch trade communications, and they were forced to seek a decision against our fleet.
FINAL NOTE
In applying the maxim of "seeking out the enemy's fleet" it should be borne in mind:—
(1) That if you seek it out with a superior force you will probably find it in a place where you cannot destroy it except at heavy cost.