Colouring uncoloured wefts/strands question

A seller on ebay is offering both pretips and wefts that have been "stripped" of colour so you can colour them yourself. Good idea i thought (saves double processing and ruining already coloured hair) but correct me if im wrong, when hair has been bleached white (and im sure this is what has been done to this hair to get it to the uncoloured stage) it is unable to be properly coloured because there is nothing left in the hair strand for the colour pigment to attach to....so this would mean you would pretty much be tinting the hair which would mean the colour would fade pretty fast.

Have i got it pretty much sussed? or do you think they have done something magical to the hair so it can be coloured properly lol

yeah i thought it was too good to be true :(

bohyme seems to be pretty good, esp with colour holding in the hair. Even though i havent used it, i would say it would be pretty good and the colour would hold.

Kristen sells Bohyme on Yourhairshop.com. and there's a huge selection of Bohyme silky straight crazy colors. She said those colors stay true, only the clip-in colors will fade after a while cos they're meant to be worn for short periods only and you don't sleep on those.
Check it out. I haven't seen the bodywave on there but I'm pretty sure she can get her hands on it.