A minor and incredibly niche effect of the rebalancing of the deep space transports, is the ability to get over 100% resists when using high meta modules in combination with the Red Giant wormhole system effect.
Entertainingly, this does not make you super tanky. It instead causes you to explode instantly upon taking any damage of the type your resist is over 100% in.
One shot from a t1 light missile.
Originally Posted by Minion
Oh hey, that's me! Saw the thread from the other day about getting >100% and wondered how the damage would calculate, so we took this old Bustard we stole some years back to a C5 Red Giant and shot it with a single Meta 0 Light Missile Launcher using T1 EM ammo from the Anathema, which would normally do ~114 damage before resistance. We mainly wondered if damage would heal you or not, but instead burst out laughing when the Anathema instapopped the poor Bustard for 12.7k damage.
Funny thing, stacking penalty actually causes you to go back down towards 100%, so you actually get "more" broken resistance by using fewer modules.
Resistance is usually calculated against the remainder to 100% with stacking penalty applied after. In this situation, we're able to break the 100% barrier by making a single huge increase in resistance that takes us over the top. Since the modules are designed with the intended math in mind and there are no hard caps on attributes to enforce sane ranges since it Shouldn't Normally Happen, the values (don't) work out as theorized, the formulas take whatever they get on faith, and Bustards get one shot.
For details, the Bustard starts with 20% EM resistance and the Pith B-Type increases EM by 59.5%. Since that's 59.5% of the remaining to 100% EM, we actually get 20% + (80% * 59.5%) = 67.6% EM without overload. A normal overload situation with the new DST bonus means +40% resist bonus, or 59.5% * 1.40 = 83.3% EM module bonus -> 20% + (80% * 83.3%) = 86.6% final EM shield resistance. As above, nothing crazy will happen since the math is still sane for the system.
Now here's the magic: C5 Red Giants have an 85% bonus to overloading, kicking DST hardener overload from 40% to 74% bonus! This means 59.5% * 1.74 = 103.53% EM module bonus while overloading, giving 20% + (80% * 103.53%) = 102.824% final EM shield resistance. One big leap through the roof.
Just like with the Magnetar tracking exploit, the stronger wormhole bonuses combined with strong ship bonuses simply push one or two variables out of the intended ranges and the math takes over from there. Unfortunately, I don't know of any formula we can use to figure out why having >100% resistance causes huge incoming damage, but maybe someone has the relevant math laying around