Yes I use leverage but my rules are around trade size rather than using a certain amount of leverage. For example (not my real numbers), if I want my stop size on TSLA to be 50c and I want to risk $100 on my trade then I want 200 shares, regardless of whether that means I'm using no leverage or all my leverage that's the trade I want to take. Of course with margin you can get yourself in serious issues if you don't trade properly and abide by your stops but that's for each individual to assess their own risk of not doing that (and if you can't then trading is probably not the right career).