On fast. a 2 population city take 2 turns to make 30 gold for a cultural blitz, that on a lonley city give 15 culture. it can be done every 5th turn.

First Civic reform cost 10 culture so it give 1.5 of a reform.

On normal it still take 2 turn for 30 gold, giving 15 culture, but can only be done every 10th turn.

first civic reform on normal cost 20 culture so it gives 3/4th of a reform.

Since costs are half on fast, it is twice as powerfull.

What it should be

Fast 2 population city take 1 turn to make 15 gold for a cultural blitz, that give 7.5 culture that is worth 3/4th of a reform.