Beresford's boast about the Russian fleet

Did admirals ever genuinely intend to fight a larger fleet with only a small portion of their available battleships?

Not normally; Beresford's claim was likely a boast, while a real commander would concentrate the full fleet rather than handicap the operation.

Beresford's claim about defeating the Russian fleet with four battleships is interpreted as a joke or political boast. Some operations need only a small force, but choosing to leave available ships behind merely to give an opponent a chance would create an unnecessary risk. An admiral would normally concentrate the fleet actually available. Even victory could prompt awkward questions if one ship suffered avoidable damage because additional support had been withheld.