thats cool that hes re-doing it for you.
but in short..yes those bends do weaken it. and many times bent tracks aren't necessary at all. especially when the bends are so extreme they dip below the axle line. im running about 6 inches of lift, I made my track bar out of 1.5x.25 dom with no bends. clears everything beautifully, and ive got less money into it then any track bar you can buy, with no worries about it breaking. and in your sliding sideways case...well that radius there is going to cause a focal point for all the stresses