A 5 foot step is a special action that can only be done in specific circumstances. Technically it is a No Action action that does not provoke an attack of opportunity. One of the restrictions on a 5 foot step is that you cannot make one in any round where you move any distance. The main two benefits of a 5 foot step is that it does not take an action and does not provoke an attack of opportunity. But it is not the only way to move 5 feet. You can always use a move action to move 5 feet.
In scenario 1 you would not be able to make a free 5 foot step, but could use a move action to move 5 feet and take still attack once. This will provoke an AoO, and prevent you from making a full attack.
In the second scenario you cannot use dodging panache. If you want to keep the option of Dodging Panache open you could use a move action for the movement instead of a 5 foot step, but that would mean you take an AoO from moving. While this may seem strange it is the only way to allow the ability to work without having to go back and redo combat.
By taking a 5 foot step action you are giving up the ability to move for the rest of the round.
the start of your turn reset all your actions. (move, standard and swift if you didn't use a swift action in your last turn and an immediate action between turns).
so in case #1 once your turn start you gain all action uses including your movement or the option to take a 5 ft step. using an immediate action before your turn doesn't prevent you from taking a move action or 5 ft step once your turn start. (it does prevent you from taking a swift action, depending if you used a swift action in your previous round or not). the immediate action in fact is accounted for your previous turn (if any) and has no movement restriction on your actions in your new turn.
to prevent you from taking a 5 ft step in your next turn, the ability need to specifically call it out to be prevented (for example see the step up feat).
in case #2 you take the immediate action in the enemy's turn, after yours was done. so again not part of your turn's movent and has nothing to do with that turn's 5ft step -and thus you may use it.(the same for that matter with the step up feat mention above)
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the only time this action would hamper your 5 ft step is if on your turn you provoke an attack of opportunity (not for moving. say from ranging in melee) and use the immediate action to move with Dodging Panache during your own turn actions. this movent will prevent you from then taking a 5 ft step until your next turn.
the start of your turn reset all your actions. (move, standard and swift if you didn't use
a swift action in your last turn andan immediate action between turns).
Minor correction. Using a swift action on your previous turn has no impact. Only the use of an immediate action between your turns consumes your upcoming turns swift action. The immediate action consuming your upcoming turns swift action occurs regardless of whether you used a swift action on your previous turn or not.
right, that was a house rule from my gm I have adopted and forgot it was one. Where you could 'save' your swift action for an immediate action before your next turn without taking the next turn's swift action. kinda like a ready action taking this turns action not the next.
Most actions take are based on turns, but the 5 foot step specifically states round. A round is a 6 seconds of time that is broken up into individual turns for each creature that can act in the round. The start of your turn will reset things from things from the last round, but not for things that happened in this round. This is not about having an action of the appropriate type free; this is about satisfying the requirement for the 5 foot step special action.
So, in scenario 1 if the attack occurred in the previous round it would you could you can use an immediate action for Dodging Panache, but doing so would prevent you from using the 5 foot step No Action for the rest of the round. You can still move 5 feet (or more) with a move action following all the rules for making a move action. Since scenario 2 specified it happens in the same round you cannot use Dodging Panache if you already took a 5 foot step.
this is obviously a mistake and they should use 'turn'.
if they meant it as the full 6 sec 'round' then the last part in the 5 ft step the op copied would mean one can take 5 ft step after his 'turn' in another person's 'turn' while on the same 'round':
"You can take a 5-foot step before, during, or after your other actions in the round."
remember it's not even an action!
talking is a free action one can use even out of 'turn', if 5 ft step isn't even an action and can be used after your actions but in the same 'round' (and not 'turn') one would be able to use it anytime he want's in that 'round' even on some1 else's 'turn'.
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I think it's a carry over form 3.5 that never got patched:
from page 144 of the 3.5 player's handbook:
"You can move 5 feet in any round when you don’t perform any other
kind of movement. Taking this 5-foot step never provokes an attack
of opportunity. You can’t take more than one 5-foot step in a round,
and you can’t take a 5-foot step in the same round when you move
any distance.
You can take a 5-foot step before, during, or after your other actions in the round."
Not an Action: Some activities are so minor that they are not even considered free actions. They literally don't take any time at all to do and are considered an inherent part of doing something else, such as nocking an arrow as part of an attack with a bow
Despite their name Not an Action is actually a type of action, They are actually listed in the book under the headings of Action Types. They are part of doing something else, so cannot be done by themselves. That means unless the action they are part of can be done when it is not your turn neither can the Not an Action action. So, you can take a 5 foot step as part of an immediate action, but not by itself.
A 5 foot step is not a quick step, it is a carful step. This is why it does not provoke an AoO.
If a GM wants to change this in his game that is his right, but at that point it is a house rule. RAW you cannot move in the same round as you take a 5 foot step.
So, you can take a 5 foot step as part of an immediate action, but not by itself.
I don't believe this is accurate. If it is, then I can cast Stone Shield to not only to get a +4 to AC against a creature, but at the same time 5' step out of its reach and avoid its attacks altogether. I think the immediate action in question would need to specifically allow a 5' step. There are 1 or maybe 2 other immediate action spells that could likewise be used, not for their intended purpose, but as a defensive 5' step trigger in the same way. (Most immediate action spells require some kind of specific triggering condition that would not occur from being attacked).
For example readied actions specifically allow a 5' step as part of the readied action (so long as you did not move during the round).
And there is the FAQ regarding creatures with trip/grab/etc abilities associated with their attacks. Prior to the FAQ it was questioned whether they got such rider effects on AoOs they made. PDT ruled that because those things are associated with their attacks, those could be taken outside of turn.
So I believe a 5' step is only allowed during your turn, unless explicit rules allow otherwise. Readied action and step up feat chain are the only ones that come to my mind. That is, non-actions still being a type of action follow the requirement of only on your turn as a general rule.
You may be right about using a 5 footstep with an immediate action. I think it is going to depend on the situation and require a GM’s call. But this does not change my point that a 5 footstep (or other Not an Action) are not standalone actions.