Years ago while gliding in Germany, my glider was very conspicuous or so i thought, being bright yellow..!!
However, when matched against against two low level F4's, approaching from slightly left of the nose, you can imagine the consequences resulting from a mid air..
Suffice to say, banking hard left towards them ( yes i know you are meant to break right, however Mk1 eyeball can see through glider floor), put the glider in a bigger plan view. My take on it was if i turn towards them, then i can see them and take further action.
Risk of collision was slight, but was there..
It was drilled into me, to maintain a good lookout, all single op aircraft have a higher workload in the cockpit, whether its a glider or jet.
With the best will in the world, collisions will happen, but hopefully with increased education/TCAS type systems and good airmanship skills, then hopefully the risk will be reduced...