Found This reply to another STO player from Al Rivera about torpedo dmg values and resits. Very good read.

The "75% torpedo penalty" is not a "torpedo penalty". It is shield innate absorption of Kinetic damage, and applies to all sources of Kinetic Damage that affect shields.

There is an order of operations that happens when the target calculates how it receives damage.

The first step that occurs is that the overall bleedthrough percentage is determined, and damage split accordingly. Damage that will go to hull is set aside.

The relevant shield facing then calculates the amount of pre-absorption and pre-resistance damage it can withstand. Any damage that would go to shields beyond this is then added to the hull damage, unmodified by any property of the shields. Then, all the damage the shields actually will take is diminished or increased as relevant by shield absorption and shield resistance and applied to the shields.

Finally, all the damage originally directed at the hull from bleedthrough is added to any extra the shields were incapable of withstanding, and that is only affected by hull resistance.

For the following examples, assume the target has a hull kinetic resistance of -50%, shield kinetic resistance of 50%, 10% default bleedthrough, and the amount of the torpedo impact before any of this happens would be 1000.

If the target has only 1 shield hitpoint in the relevant facing:

First, the bleedthrough percentage is determined to be 10%. 100 damage is going to be directed at the hull from this, and 900 at shields.

The shields determine that they can only withstand 8 pre-mitigation damage, and set the remaining 892 aside to hull

The shields take that 8, the shield absorption decreases it to 2, and the shield resistance takes it down to 1. The shields then take 1 damage and the shield facing is now 0.

The hull damage before resistances is 100+the 892 the shields could not withstand, for 992 of the 1000 pre-resistance damage. Hull resistance of -50% is applied to this, and the hull takes 1488 damage.

If the target has 100 shield hitpoints in the relevant facing:

First, the bleedthrough percentage is determined to be 10%. 100 damage is going to be directed at the hull from this, and 900 at shields.

The shields determine that they can only withstand 800 pre-mitigation damage, and set the remaining 100 aside to hull

The shields take that 800, the shield absorption decreases it to 200, and the shield resistance takes it down to 100. The shields then take 100 damage and the shield facing is now 0.

The hull damage before resistances is 100+the 100 the shields could not withstand, for 200 of the 1000 pre-resistance damage. Hull resistance of -50% is applied to this, and the hull takes 300 damage.

If the target has 1000 shield hitpoints in the relevant facing:

First, the bleedthrough percentage is determined to be 10%. 100 damage is going to be directed at the hull from this, and 900 at shields.

The shields determine that they can withstand 8000 pre-mitigation damage. This is more than is directed at them.

The shields take the 900 directed at them, the shield absorption decreases it to 225, and the shield resistance takes it down to 112.5. The shields then take 112.5 damage and the shield facing is now 887.5.

The hull damage before resistances is 100 of the 1000 pre-resistance damage. Hull resistance of -50% is applied to this, and the hull takes 150 damage.

For context, if those 3 examples happened with an energy weapon:

For the following examples, assume the target has a hull phaser resistance of -50%, shield phaser resistance of 50%, 10% default bleedthrough, and the amount of the phaser cannon impact before any of this happens would be 1000.

If the target has only 1 shield hitpoint in the relevant facing:

First, the bleedthrough percentage is determined to be 10%. 100 damage is going to be directed at the hull from this, and 900 at shields.

The shields determine that they can only withstand 2 pre-mitigation damage, and set the remaining 898 aside to hull

The shields take that 2 and the shield resistance takes it down to 1. The shields then take 1 damage and the shield facing is now 0.

The hull damage before resistances is 100+the 898 the shields could not withstand, for 998 of the 1000 pre-resistance damage. Hull resistance of -50% is applied to this, and the hull takes 1497 damage.

If the target has 100 shield hitpoints in the relevant facing:

First, the bleedthrough percentage is determined to be 10%. 100 damage is going to be directed at the hull from this, and 900 at shields.

The shields determine that they can only withstand 200 pre-mitigation damage, and set the remaining 700 aside to hull

The shields take that 200, the shield absorption decreases it to 200, and the shield resistance takes it down to 100. The shields then take 100 damage and the shield facing is now 0.

The hull damage before resistances is 100+the 700 the shields could not withstand, for 900 of the 1000 pre-resistance damage. Hull resistance of -50% is applied to this, and the hull takes 898.5 damage.

If the target has 1000 shield hitpoints in the relevant facing:

First, the bleedthrough percentage is determined to be 10%. 100 damage is going to be directed at the hull from this, and 900 at shields.

The shields determine that they can withstand 2000 pre-mitigation damage. This is more than is directed at them.

The shields take the 900 directed at them and the shield resistance takes it down to 450. The shields then take 450 damage and the shield facing is now 500.

The hull damage before resistances is 100 of the 1000 pre-resistance damage. Hull resistance of -50% is applied to this, and the hull takes 150 damage.

As you can see, if the impact is not enough to collapse the shields, the torpedo and the energy weapon deal the same damage to hull, and if the target has a literal sliver of shields, the damage to hull is almost identical.