Too easy to strafe-run into your own projectiles and damage or kill yourself.
Ever since the projectile collision code has been re-worked, it's been far too easy to strafe-run into your own projectiles (especially slow ones like the RPG, Devastator, and Shrinker), causing you to damage or kill yourself.
Video demonstrating the issue: http://shadowmavericks.com/files/ShareX/RPGClipping.mp4