So I’m a expert on Gaige and I can’t really tell something so if I have blood soaked shields does that work or go against fancy mathematics if I have a Fable tortoise shield
Not a Gaige expert but this from the wiki on fancy mathematics - " It improves shield recharge delay and recharge rate based on how low her health is. It does not improve either stat in any way when Gaige’s health is full. This ability works wonderfully with the Blood Soaked Shields as it provides highest yield toward a Mechromancer with low health status.
A Neogenator or Evolution provides increased health regeneration when shields are low. When combined with this skill, both health and shields enjoy high regeneration when Gaige is near death."
I would imagine if you have 500 health or 500,000 health if your health is full, it’s full, no matter what the value, and obviously the same with low health if that makes sense. So based on that i would think a higher health value would possibly be better than a lower one. Like i said not an expert with her but hope that helped, if not, soz 
Thank you so much
It doesn’t really matter.
BSS takes a % of health, and fancy math activates at a certain % threshold (what it is I don’t reacall, let’s just say 15% for now), so it doesn’t matter whether you have 100 or 1000000 health. FM will activate whenever your health bar reaches that % value.