I had read with great interest the Haag's level 10 excursion. He seemed to get bored with the tactic, though - and eventually it would have run out of steam thanks to the energy reactor's declining return mechanic. (OK, pun intended.)
Yup...I got bored. I could have continued if the enemy did not have Electric Shuttles, as these are quite efficient counters. So I tractored 100 ships, moved them off somewhere, sort out the electric shuttles from the rest (the boring part), drag of all the rest in groups of 25 or so to parasites, repeat. Wait until you have about 100 electric shuttles, drag them to a safe distance of a group of cruisers, kill them from long range. It takes quite a while to kill 2000 ships this way, and then you could move in with the fleet and kill 1000 cloaked ships and 1000 turrets or so. And this was before the mega-raid system, and at AI-10 the planets fill up so fast that they generate a raid/hour/adjacent planet or so and there is no way to defend against that kind of firepower.
My favorite way to use Etherjets now is:
a) you want to steal cruisers. Cruisers are durable and fire at long range so they kill everything before it fires back. You can never have too many cruisers. I Cruisers are not so good, but II, III and especially IV cruisers rule. You want to have more III and IV cruisers than your build limit, preferably much more. Then you need to preserve these, as they can
b) setup a trap somewhere, far away from your cruisers (they will kill everything that comes into range). The trap is ideally behind a wormhole, as this will cause no interference of other enemy units. The trap will contain some II/III engineers for healing, as many parasites as you can spare, a few tractor turrets to prevent runaways and all of your I fighters (these do a lot of damage against cruisers and are generally quite worthless), plus one or two factories producing more parasites and I fighters.
c) move up a bunch (30 or so) Etherjets in stealth mode very close to a clump (20 or so) of enemy cruisers, in such a way that the cruisers are between your Etherjets and the trap.
d) select all your Etherjets and target the closest cruiser. Now they will decloak.
e) a split second later, move all your Etherjets to the trap (if you have a wormhole trap, just hit TAB and click on the planet with the trap)
Step e) causes your Jets to fly "through" the enemy cruisers, and thereby tractor most/all of them, and then move to the trap. After step e, this should be in fire-and-forget mode, allowing you to select a new bunch of Etherjets.
You want to end up with a lot more III and especially IV cruisers then your build limit, as this is the only way to increase the size of your fleet in a meaningful way. And then you will want to preserve these, since you can only rebuild up to your build limit. So, you want to take all other troops to take the bulk of enemy fire: III/IVs do never go first through wormholes, they tend to stay at the back of the pack during big engagements etc.
Other targets for this tactic are IV fighters and certain specials that you like to have (high level space tanks, tachyon fighters, MLRSs and munitions boosters).
Lower level fighters are not worth it, and bombers are relatively resistant against this tactic, as the parasite attacks have trouble with penetrating bomber shields.
