The land route to the wyvern legion (via the Tower and azure ones) was shorter than sailing by sea (after all, there were some strong logisticians among the heroes, but navigation was a disaster). Therefore, in order to wipe out the wyverns, one would have had to drag themselves toward them anyway—and in terms of time, this would have taken quite a lot even with the use of whirlpools...
So not particularly much extra time was spent on the pedestrian expedition... The Archs, in turn, helped a lot in the Conflux. If it weren't for them, I don't even know what would have been left for the fight against the CDs. That fight was the last one.
But that is all in the past now... :)
