ICK!!
1st-off.
It isn't Whitney's I will always Love You. It's Dolly Parton's song.
2nd. Dolly sings it much better than Whitney.
3rd. I suspect you think that OVER singing is good. It's NOT!
Good singers accentuate the song, making the song the focus. Whitney (and many many others!!!) make themselves the focus, They warble, vary tempo and pitch, even alter the melody ALL to bring attention to themselves (or their Voice!).
That is NOT good singing IMO.
I give you Celine Dion as an example. This is a free country. You can listen to anything you want to, But you won't convince someone like me (who listens to all types of music for about 25 - 30 hours intensely every week.) that Celine Dion is a quality singer. She can sing sure, but I wouldn't waste 42 seconds of my life listening to what she "sings". Life is too short and she's just awful. Same with Whitney for the most part!