This is most certainly the best advice you can give to someone coming from other languages. I constantly see people I very much respect for their skills in other programming disciplines get very angry and make otherwise irrational rants about Haskell because they can't translate their hard won skills over to this new model. Learning Haskell will make one feel like a beginner again, should just embrace that from the start.
Sounds kind of miserable, right?
That's why you should also prepare for it with some of that early curiosity and wonder that drove us all to learn programming to begin with.
Haskell is probably unlike anything you've used before.