weapons power over 125 gives you a few shots that dont drain you below 125, and all deal damage at the 125 modifier. all the following shots that do go below 125 are being fired at a higher energy level then they would have other wise too. this works with beams, AND cannons in my experience. simple tests showed cannons not benefiting from it, but eyeballing how low my energy drops with a full load out of cannons showed there was a difference.

here's an in depth log parsing of the actual benefit

https://docs.google.com/spreadsheet/...0E&output=html