You are right bro 2-3 times a week MAX the abs need to recover as well as any other body part.People have a misunderstanding that if you train the abs harder they will finally show......nope you need diet and cardio for that but also remember that if you workout your abs are used for every ex performed.

Next time you do leg ext as you lift the weight up crunch your abs at the same time I find I get hell of a burn as you hold the crunch for as long as you do the weight.

Billy