[MutantGene]

Unsure where to ask this question so we'll try here, I've been playing the game for many months and have recently started a multi-player game

I keep thinking I have this simultaneous movement stuff figured out when along comes something even more idiotic...
Picture this if you can, within a system (adjacent to each other)

f (enemy fleet)
* (my planet with large fleet)

I give orders to my ships to seek after the enemy ships (two of mine after each of his, just incase they split up)

my ships move first onto his fleet
his ships move second onto my planet
day 5 - combat starts, hmm.. no enemy for my ships to attack
oh look there's an undefended planet for his fleet, lets blow it up!

sometime later in the month we seem to catch up with him and extract revenge, Gggrrreat!

How are you suposed to get this to work? How can you reliably attack enemy fleets that move the same speed as you? (looks like it only works if you are an even number of spaces apart )