I never knew that!
I assumed Thor'ss power all came from his Hammer until this movie (since he had no powers in the original Thor until his 'sacrifice' proved himself worthy)
No your absolutely right, in the original story, Odin in an effort to teach his son humility and responsibility bound Thor's power to Mjolni. While he was in Midgard he could only become Thor as long as he touched the hammer if 60 seconds passes without contact he would revert back to his mortal persona. Which leads the hammer's abilty, anyone
who is worthy can become Thor
Ie Thinderstrike, beta ray bill, female Thor, Volstagg etc
Like Marvel comics they keep changing it so I guess in the MCU they decided to 'simplify' it even further which I have mixed feelings about, I hope they are smart with this because Mjolni is the centre piece to Thor.