sorry, i forgot to put above, the photo is from www.rachel-bilson.org 


I think those reddish ends can safely turn the idea into disaster.. it just doesn't look taken-care-of.. I've too had darker roots plus a faded color in the ends and it looks like all the opposite of this... I like the idea of an accidental exposure to the sun but I think the trick in pulling it off is to make it look intentional.. like Alexa's or Isabelle's.i have two-tone hair as a result of built-up hair dye and i absolutely hate it! for me, it looks really unhealthy as i have dark brown hair naturally, and then the ends are this reddy gingery colour - it just doesn't look great. however in some of the pictures posted it definitely can work for some people!
i agree that the hair needs to be really healthy, i think if the ends are split or fried the whole thing just looks tacky. i also think it needs to be pretty subtle and look natural.. even if it isn't. 
i see perhaps you too are now a quiet fan of her incredible beauty..
though i can't help but wonder if it would look any good if she wasn't so bloody pretty..
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Why blondettes have more fun: How to achieve the low-maintenance look as sported by Gisele and Jen
You might not have heard of blonette (or blondette, depending on who you talk to), but it's pretty much the only hair colour to be sporting right now.
It might once have been called dirty blonde, or sunkissed brunette, but now that it's being showcased by the likes of Gisele Bundchen and Jennifer Aniston, it's got its own fashion name.
If you want to try it, bear in mind that you need to work with what you've got.
'Brunettes should ask their stylist for chunkier pieces of colour, rather than fine highlights, and you want to go for a gradually toned look that's blonder at the front but blends darker at the back,' explains Carmel Blackburne, colourist at John Frieda.
'Blondes will have dark sections put in, but it's subtler than previous colour jobs. The idea is to avoid that block look at the roots when you're growing it out. It's more low maintenance.'


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they just couldn't make it look natural..it was like she divided the hair into 2 section and bleached the lower part
sooo ugly