Not always. You telling me that a larger force of TL10 vs a smaller force of TL15 ships is always going to win? I don't accept that.
Fine. "Superior" force, for whatever definition of superior you want to come up with. The specific point being that it's an issue of sheer numbers, and the environment itself offer zero or few force multipliers that one might expect in a typical land engagement where defenders can have great advantages over attackers.
Only in deep space. In an inner system there are multiple objects that create overlapping gravity wells which lead to Lagrange points and other hazards that good commander can take advantage of.
Lagrange points? You think a ship with a 4G drive gives a flying potato about a Lagrange point? Maybe if you're using thrusters little improved over the aerosol spray can, but Traveller ships have ample, cheap thrust. Getting a free hex or two of velocity via a slingshot may have it's applications, but in the big picture, it's not going to be a major factor in an engagement of any real size. The guns still bear, the ships are still in range of each other. Unless being close to the planet blinds the other ships sensors (and in contrast does not blind your own), there's pretty much minimal tactical value.
You are also leaving out the skill of the commanders.
A commander might well improve the capability of a specific ship by a Diff mod or so, but it's not necessarily enough to turn the tide in any particular engagement. If we're talking mano a mano, ship on ship, sure it can be an advantage. But in the end, in a fleet engagement the contribution is marginal, and one on one good commanders die from lucky hits as readily as bad commanders.
A commanders value may be in being able to rally the crew when things turn sour, but as a general rule, naval ships don't have "morale" like infantry squads do, and ships don't really degrade over time, they're either mostly functional or combat ineffective all at once.
Also, just because your sensors can detect moving objects at long range doesn't mean you know what they are. Is that formation of IR Sources that just made a jump into your home outer system Large Freighters and Tankers masquerading as a Fleet? Or is it a group of cruisers? Based on that information do you start maneuvers now, or do you wait until those units get closer in system for ID before maneuvering your defense?
Who knows? Who cares? Those are pre-combat decision points. Send out a scout.
On the other side of the coin when you jump into a system, you detect some ships in orbit of the GG and the primary world. Do you commit to a burn toward the GG with most of your Fleet? or are those ships in orbit of the main system a Fleet strong enough and fast enough to punch holes in a raiding ship group heading for the GG?
Depends on what the initial target was based on intelligence estimates that are at least 2 weeks old. Are you hitting "old men and children" or did a SS Panzer Division suddenly show up making your "thunderclap surprise" a "Bridge too far". Whatever your target is, you're going to jump in as close as you can taking in to consideration the 100D limit and however long it takes to assemble the fleet and implied travel times of responders to initial entry (I'll refer you to the other 10,000 post message threads about jump travel to discern how tight a fleet can jump in to a system). If you can jump in at the same time, with everyone arriving at once, you'll hit as close to the 100D limit as you practically can. The longer it takes for the fleet to arrive, the farther out you'd enter so you can assemble your forces safely.
For reference, at roughly their closest point, it take almost 70hrs (~3 days) for a fleet to get from Earth to Jupiter with a 4G drive. In TNE it would be far longer since in TNE ships are fuel limited and won't burn the entire trip.
The other ships at the other part of the system likely won't even be a factor in the initial assault unless it takes days to assemble the attack force. Then you may as well consider the two in system fleets as a single force since they'll likely rally together to meet the threat.
Single ships die when up against larger forces. (Reference "Superior(tm)" force always wins.) There's little motivation to split up your forces when attacking. You want to consolidate as quickly as possible. "Skirmishers" don't make any sense, that's an intelligence operation. A smaller fleet can delay a larger fleet, maybe, but if the sizes are disproportionate, not for very long. The main fleet may have its vector plotted for its ultimate destination and simply march along that path, pivoting the ship to bring its guns to bear to attack the delaying fleet while flying right by or through it, never even slowing down.
If an attacking fleet has a vector magnitude of, say, 20 hexes (2 light seconds per turn), they'll be in and out of range of an intercepting fleet for only a couple of rounds of fire. Better for the delaying fleet to grok the attack vector, park on the side, and catch up from behind, but then they'll be clawing in to range and taking fire. (If I can hit you, you can hit me.) At best they'll consume missile stores of the attacking fleet while the larger force eats the smaller force. Not sure if that action is worth the cost.
But this was all gone over in the intelligence briefings, where the timing of the attack, force composition, mission parameters etc. were determined. And has nothing to do with combat.
That's operations.
