At the beginning of a game (or when an empire starts fighting a defensive war), there is a tendency to want to defend everywhere at once. A good player will not do this since "he who defends all, defends none" and consolidates his fleets into a few defensible positions to avoid being spread too thin. When an offensive is mounted into this territory, there is a tendency to tackle these heavily-defended positions as they are encountered. While this approach does have some merit, it can lead to large attrition battles, sapping hull strength and bogging down an offensive to the point of handing over the initiative.

By using the methods developed in the South Pacific during the mid-20th century, you can "Island Hop" to achieve your objectives and still retain momentum.

When a strongpoint is encountered, enough ship equivalents must be kept on station to pin the force at the strongpoint. Every chance that arises (on your turn or if you are able to react into the strongpoint hex on your opponent's turn) you must attack that strongpoint. Scoring a SIDS / PDU step or even just targeting a key unit in his fleet on one round of the approach battle will "keep him honest" - concerned about your true intentions toward the target - which is NOT taking it down - yet.

The advantage to this is that it takes fewer hulls to pin or merely threaten a strongpoint than to take it, freeing up more of your ships to go hit other less defended, or undefended, targets. While you are pinning his fleet in a battle you do not need to win (for the moment) the rest of your ships are hitting everything they can reach.

Occasionally, some ships may strike easy targets so deep they go out of supply. This is an acceptable risk. After a time, the position will be cut off and the pinning fleet can be bolstered by new construction or some of the other fleets used on the initial offensive can fall back to launch an assault on the strongpoint.

When his losses are no longer worth defending the position, he will abandon it or give it up in battle for relatively few losses; if he stays past this point, even better for you. Eventually, this tactic will become impossible as the number of targets shrink down to just the home systems, but until then, it can be effectively employed. The difficult part in using this tactic is enduring the idea of leaving an enemy supply point / fleet in your rear areas or along tenuous supply paths, so steps must be taken to counter potential moves along those lines. If you can stomach this, however, the payoff can be huge. Now get hopping!