@Jordon i think that "once per turn" is the "larger" version of "once per activation", and as the activation hasn't changed to another model, you're still in real colette's activation, hence "once per turn" here also blocks you from doing it more than once per activation, and IF you've already done it with real colette/another dove/decoy then you can't do it again...
@Maniacal_cackle I don't see the same problem as you... a marker cannot take damage, so while you say it takes lethal damage, it doesn't matter as it is reverts to being a marker once the action ends and a marker cannot die/sustain damage/have conditions etc. Furthermore why make a point of it being three attacks... it's three seperate actions and between each action you revert to the marker being a marker, so it's pointless to talk about one/two/three attacks, as it doesn't matter.
@Maladroit I agree, though I do not think the dove is a dove during the action, so it can sustain more than 2 damage, then when the action ends and pseudo colette as you call her (I like that choice of words) reverts to a dove, the dove sustains the damage then and dies if 2 or damage was given to it while being colette.
And I still hold to the argument, that the marker/dove is not a marker/dove during the action so it has mv 6, is significant, has don't mind me etc... how else could it take an action. I really think people are overcomplicating this... same way, how is cassandra a problem, once she takes the action routine performance it is she that is the model and reference for the action and hence she is "this model", so colette card is not in play during cassandras activation for any other part than copying "routine performance"...