Judo throws are taught, but aren't a focus. Most BJJ takedowns teach how to firstly clinch without being hit, then generally trip the opponent for the takedown. They are easy to learn and can be quickly applied against an opponent unskilled in grappling arts. The problem with some Judo throws is that a) you have to turn your back on your opponent for a lot of them and b) they require a lot of finess to work. In a fight against someone unskilled in grappling, once you clinch and attach your body to theirs it's easy to take them down, without risk of being struck. If you try a Judo throw then you're usually at striking distance. Judo throws work, there's no doubt about that. They do take time to make them work however, and Kano recognised this which is why he wanted people to concentrate on throwing before ne-waza (He says this in one of his books, I can't remember which). More and more BJJ schools actually now focus on wrestling takedowns, because it's immediately applicable to no-gi, and MMA, as well as also working with a gi. P.S For Judo followers, please note that I am not saying Judo throws don't work. They obviously do and can be very effective in a fight if you throw someone hard onto concrete. However, it's a longer process learning this against an opponent who strikes than learning how to bodylock and clinch.