I actually agree.
I am not claiming her to be a great or even a good actress. She is somewhere b/w below average and average. However she does have strengths in some areas. Her job is to look pretty, make some colorful expressions, light up the screen with her megawatt smile, dance like a dream and bring butts to the cinema hall... and she always succeeded with that. She is also smart in her script selection - she knows her limitations and therefore almost always chose scripts which suited her - basically flowerpotty roles whose main essence was to look good.
Watch Sonam in some of her songs, you'd know how inadequate Sonam is in giving these 'candyfloss/flowerpotty' expressions. Even great actresses like Tabu looked out of place in commercial roles. Vidya was horrendous in Hey Baby etc. But Katrina looks completely right in these 'flowerpot roles', where your job is to look pretty, make some colorful expressions and dance like a dream. It's not acting, but you still need some theatrical skills to do them.
So while she is not great actress, she does have some skills .
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