Pretty sure that FD wrote the book on how shields work. I was interested in an explanation, rather than a CV. Mathematically, if the regen rate is the same (which it is), then you want to go for the shield combination that gives you greatest protection for each of the damage types - and in this case, it will be the heavy duty. The only reason that you are getting different regen rates is because you are calculating it backwards, as far as I can see - and the only conclusion from that is that small shields regenerate quicker (which is obvious). However, if the regen rate is the same for two shields, then the only difference is that the smaller shield will go up and down more often than the bigger one - it doesn't provide better protection overall.
Ok. I'm at my desktop now, so I can give you numbers. First, let's consider the heavy duty build. This is with a single booster, providing 58% shield boost:
Heavy Duty | | | | |
| Absolute | Thermal | Kinetic | Explosive |
Regen Rate | 1.80 | 3.00 | 2.40 | 3.61 |
Broken Regen | 3.80 | 6.34 | 5.07 | 7.61 |
Health | 287.0 | 479.0 | 383.0 | 575.0 |
First data column is the absolute numbers. The following three columns are the
effective health, after considering resistances. That's how much damage of the given damage type it would take to break the shield. Just like shield health, we can also calculate
effective recharge rates. Yes you're only regenerating 1.8MJ of absolute shielding, but because of resistances, that's effectively 3/2.4/3.61 MJ of shielding when facing thermal, kinetic, and explosive attacks respectively.
Now let's look at a resistance build. This is with a single grade-A booster, providing 20% shield boost, and 17% resistances across the board:
Resistance Augmented
| | | | |
| Absolute | Thermal | Kinetic | Explosive |
Regen Rate | 1.80 | 3.62 | 2.89 | 4.34 |
Broken Regen | 3.80 | 7.63 | 6.10 | 9.17 |
Health | 218.0 | 438.0 | 350.0 | 526.0 |
You'll notice that all the health values are lower, especially the absolute health. You'll also notice that the absolute regen rate is the same: 1.8. The important thing here though are the effective recharge rates. 3.62 vs 3 (20% better), 2.89 vs. 2.4 (20% better), and 4.34 vs. 3.61 (20% better). Since the viper IV is a small maneuverable ship with a relatively small speed, recharge rate is extremely important. Since a resistance augmented booster gives you 20% faster
effective recharge rate, I find it to be the superior option for the ship. In a prolonged fight, the increased effective recharge rate can fairly quickly outstrip the benefit of a higher starting capacity. Once the extra capacity offered by the heavy duty booster has been depleted (which doesn't take that long, since the shield is still fairly small), its contribution to the rest of the fight is extremely limited. A resistance augmented booster continues to provide extra durability for every moment the shield is up.
In a small ship (like the viper IV) whos shield is likely going to drop and reform several times in a serious fight, starting out with slightly more shielding is nowhere near as important as having a higher recharge rate.