Irreversable Choices

In developing a character in GW, the only irreversable choice (after choosing primary class) I can come up with is when to leave Pre-searing. Customizing a weapon is irreversable, but that's not a choice made in developing a character. I've yet to make it to 20, so I've not a complete list of the choices to be made. Are there any choices coming up that you could add to this very short list?

Can you change your secondary class more than once? Can you change it back if you change out of one?

you can change your secondary multiple times

I know you can change your secondary class, however, I don't know if you can change back, nor do I know if you can change back again if you have done the quest to change it already

EX. Nec/Mes gets Nec/War then decides he wants to be Nec/Mes again. Not sure if that's possible. Nor do I know if it's possible for them to become Nec/War more than once either.

Multiple times to various classes once, or can you switch back and forth freely?

according to GW you can have a character that has switched to every secondary there is

edit

it was stated that the player would have a character with a rich and varied RP history and made no note of limits on changes

I'm not surprised about that. the question is can you go back? Like could you be a 2nd War then 2nd Ele then 2nd Mes then 2nd Ele again then 2nd Monk and then 2nd Ele again.

Yeah, I'm wondering too, because I want to switch from mesmer -> all the other classes -> then back to mesmer again, is that possible. Also, can you do it after ascension? Most of the elites are post ascension =/

yes you can switch back and forth freely, but you have to complete your original secondary professions quest before you can pick it again.

So once you complete the 5 different quests for the 5 different secondaries, you can switch back and forth without penalty any time you want?