This is true, but not all 10000k bulbs are created equally. Ya gotta look at the spectral output of all the bulbs because some have a better chance at being useful for horticulture. For example, the hortilux blue bulbs are actually rated at 7400k because they are considered an almost pure white light. If you look at the spectral analysis, however, you will see that it falls a bit short at the 460nm wavelength which sucks balls. There are some 10000k bulbs out there that put out a hefty spike at 460nm and also contain quite a bit of red and other colors so do some research before buying into the advertising bullshit that is everywhere. I've been experimenting with all kinds of light for the last 10 years and have found that no matter what type of bullshit light you use, if you add a bunch of deep red LED's to your lighting your growth is gonna accelerate 10 fold. 460nm and 660nm are the key wavelengths, but it's not an exact science because plants adapt REALLY well to crappy light sources such as HPS and MH.