A skald is a cross between barbarian and bard. They are able to give others (and themselves) a psudo-rage using a bard-like ability.
Rage Powers - 3rd level
At 3rd level and every 3 levels thereafter, a skald learns a rage power that affects the skald and any allies under the influence of his inspired rage. This cannot be a rage power that requires the creature to spend a standard action or rounds of rage to activate it. For example, the skald cannot choose terrifying howl (which requires a standard action to activate), but can choose knockback (which is made in place of a melee attack).
Ok, so thats pretty clear that you cant grant rage powers that take a standard action to activate.
If a rage power can only be used a certain number of times per day or per rage (such as renewed vigor), each ally affected by the inspired rage song is subject to that limit (with once per rage abilities limited to once per inspired rage).
Hmm, renewed vigor
Benefit: As a standard action, the barbarian heals 1d8 points of damage + her Constitution modifier. For every four levels the barbarian has attained above 4th, this amount of damage healed increases by 1d8, to a maximum of 5d8 at 20th level.
Ok, that seems fine...wait its a standard action to activate! So why would they use an ability that is not allowed as an example?
So which is it? Is renewed vigor a special case? Are all rage powers that require standard actions to activate allowed? Did they somehow make a mistake with this very specific example of how the ability works?