He means, if there is golden sunlight and you white balance for the snow, the snow will be white instead of golden, and everything else will have a blue tint.
If the snow is white, white balance with the snow, sure. But if the situation is different, use a grey or white piece of paper. If you're really want to get it perfect, carry a gray card.
OR if you're shooting at night with flashes as primarly lights, just put it on the flash preset. If the flashes are there for backlight or accents, try to balance for the main light, be it ambient or an incandescent bulb or anything, and then gel your flashes to match that color so it looks good in the photo.