Yes, I’m aware of these tricks. In fact, I’m running my simulations at the moment using online parenthesis evaluation. In addition, I have used bounding boxes as often as possible. The original goal behind the expansion of my regions is not only to increase the speed of my simulations but also to check, if nested parenthesis could cause precision errors as reported in this post Unexpected GEOFAR tracking errors. From your experience, could nested parenthesis together with online parenthesis evaluation cause numerical precision errors?