At least 20 olive trees near the Bing Nursery School at Escondido/ Rosen. I found them late (last month) and most of the olives were already on the ground or shriveled on the trees. I am no olive expert so couldn’t tell how well they taste- perhaps next year I will brine a few jars and see.
This year I found a branch with a hook at the end and used that to get myself a haul of about 15 persimmons. Score! But yes the tool you described would work much better.