What's Nano Jumping?
You know, when a ship is in a battle and then suddenly it jumps out and reappears near a weaker part of a ship. For Example, in a (Made up by me) user-made campaign:
A Colossus is in a fight with a Sathanas, the Sathanas is at 75% hull and the Colossus is at 25% Hull, the Colossus jumps out and ends up behind the Sathanas, shoots a BFGreen at the LRed on the Sathanas's arse and then proceeds to toast the Sathanas.
Why is this Stupid?
Because if the Colossus did that then the Sathanas would just enter subspace and emerge facing the Colossus again. The Colossus wouldn't be able to move behid the Sath because it would need to recharge its jump drives.
Nano Jumping almost always puts you at a disadvantage.
Almost?
Well I'll give another example, this time from Inferno.
The EASD Nemesis (A big nasty ÜberDestroyer) is alreaady in the area and then the GTCa Independence (A semi-Juggernaught) enters the battle area in a good position to destroy the Nemesis (Nasty ÜberDestroyer). The Nemesis then jumps out and emerges on a weaker flank of the Indepence (Semi-Jugg) The player then has to destroy some beam cannons on the Nemesis. The reason a nano-jump would be advantageous to the Nemesisis because the Independence has just arrived and has no energy left in its subspace drives so it can't just nano-jump into a better position.