Why does Inspiration primary provide such varied stats in gold efficiency?

It's not a big deal but the 20% AS seems to be a bigger value than for the bonus stats Inspiration gives in the other trees. For example, Precision primary gives 18% AS or 450g and that makes you come ahead by 50g in terms of just AS (obviously you miss some other important masteries). On the other hand, Resolve primary gives 130 HP and Inspiration/Resolve only gives you 15 more HP. This means that Resolve primary give 347g and Inspiration/Resolve 387g. This is 10g less than the AS one. I've seen this taking Sorcery/Domination too. You'd get 11 AD from Domination primary and you et 16 AD from Inspiration/Domination. This is a whopping 175g more of AD but only 35g more compared to Sorcery primary. I guess they consider the Domination masteries so powerful that you cannot have comparable values. I've rambled a lot. I'm just trying to understand how these were decided.

For ADs, the most value seems to be from Domination/Sorcery secondary at 560g. Precision comes second at 500g. For AP, you get even more value from Domination/Sorcery. It goes up to 587.25g. _By comparrison, Inspiration/Resolve is a pathetic 387g of HP. _