does this mean i can 5'step +5'Step +1 tick delay as a 3 tick action (2 with quick) ?

Yes. You can combine incidental with delay.

You just can't incidental by itself. Reason being, some people with quick and low paces were moving faster 10' stepping than if they were using regular move actions. Also, there was a lot of strain recovery cheese with incidentalling by itself.

To word it correctly, your declared 'action' is Delay, you can then choose incidental movement and one other trivial/simple skill action to add on top of that (potentially making a Delay worth up to 5 ticks including 10' of movement).