You’re not swapping specs then, you’re swapping runes. Thats a tall claim that its never happened outside world first race guilds. Retail is just a different beast, their talents aren’t like dual spec at all. The main example is probably from another version that has the same dual spec system, wrath.
Personally, if they add dual spec which I think they will, I want to see free to cheaper respecs at trainer with dual spec swap at rested areas or trainers.