The reason you can respec at anytime is because you are a doppelganger, who is tricked into thinking you are who you are- I wrote a theory about this a few months earlier, can find and read it under my profile. Dopplers abilities always are what they mimick, a doppler that is connected to a mindflayer hivemind has the ability to pull from any source of hero abilities and specs that they have ever enslaved. The tadpole is that direct link. AKA when you respec it will likely be because the tadpole overwrites your conscious mind.
That's an interesting theory. It solves the story problem with respec'ing that some folks have a big issue with, but it introduces its own problem. If the 'pole is a reasonable in-game explanation for respecing, that means we can't trust any perception as true. If we can't know what's true and what's not, that's a problem. If a game is going to have epistemological ambiguity, that would have to be a core focus of the story, not a consequence of an explanation for a player-retention-focused mechanic.
