I like your funny magic words man. No more seriously I think I get the idea thanks for the post and details.
I’m a noob at shaders and GPU programming too. Have you looked at Github issues on the Godot repo? And maybe opening a new one. It would get you ideas and answers from people with the required knowledge I think. We aren’t the only people who want/need this data from GPUParticles. The official Discord server also is active.