Ok, to be more specific:
In Mando Raiders do you really think getting to a point where the bonus boss can do absolutely nothing to your group and you can safely kill him is just using the environment to your advantage? I definitely don't think so,
If you want to get technical, the boss will still do damage to DPS/healer when he would be doing his leap, right before he turns on his red circle of doom. The only thing being on the wing does is prevent the tank from taking any damage (since the boss can't reach) or the melee from taking damage from the red circle (since it doesn't reach down).
If the devs really cared, they could give him a harpoon to use when his primary target is out of melee range when he's not in red-circle-of-doom phase.
This is one of the things that gets brought up a lot with the cheesing of mechanics: they wouldn't be all that hard to fix if the devs felt like fixing them. If the devs don't feel like fixing them, it's either intended or unimportant. If it's intended, they're likely to applaud us for learning so quickly. If it's unimportant (which is my guess), they probably look down on the practice but consider it to have no real effect upon the game. As I see it, the none of the bonus bosses are even remotely hard, since they're tank/spank + one interesting mechanic; if you're going to wipe, it'll be on the final boss (or, for some FPs, one of the middle bosses like the Boarding Party) since they actually have more complex mechanics and generally hit harder to boot. The bonus bosses are just mechanisms to provide the bonus loot for killing trash.