another "does it make sense to...?" question
Particularly when low on energy, firing very low power bullets makes sense because they're faster (easier to hit with) and give you more chances to land some shots and stage a comeback. The opponent could be firing higher power bullets, miss a few shots, and you're right back in it. So I wouldn't completely restrict myself from going below 1.7, but that sounds like a reasonable setup until you get low on energy.