Pure Defensive Systems and Hull and Shields?? how would this work

It would take a lot more energy to kill you, but people could still do it instantly by speed-clicking since they wouldn't have to repair.

Yeah, turtling is more a method of telling someone they'll have to waste a lot of time and power to take you down, and thus aren't worth their while. It's debatable how effective that really is.

I'd go so far as to say it just plain would not work. Using cloak to mostly stay off the battle list is probably what the OP is looking for.

Alternatively, going on the offensive and getting in loads of kills will deter those looking for easy kills. And you get something for your effort. And it's a ton more fun than stressing about getting attacked.

And a defensive build won't help when planets get stolen, which eventually happens to almost everybody.

In closing, my standard reply to those looking for defensive builds is "Have you tried Farmville?"

the best turtle in this game is not a turtle, but the Munchkin who never builds decks beyond what is needed for a single max tech Hull module. By hiding behind the damage cap and splitting rank points into engineers and tactical officers, this Munchkin build would have little difficulty taking on all comers