I didn't say that Cipher doesn't work but that it is only better than Smithy if you actually use the "spend an Action" option.
Village and Smithy is the equivalent of two Labs, the combo is non-terminal. Village and Cipher triggered on the other is a massive terminal draw (with discarding or final topdecking). You draw a lot but are out of actions ... unless your starting hand featured two villages.
So unless there are double villages like Port, Fishing Village, Bustling Village or your deck has an incredibly high village density you cannot play a triggered Cipher with other Action cards in your deck.
You don't need to playtest this stuff, it is just how the card mechanically works: you need 2 Actions to trigger it.
Of course there can be a Kingdom in which you play village and Cipher without the second option being triggered ... but then the card is weaker than Smithy and we should reconsider the price.
This is after all how this entire discussion started, with balance considerations. The problem is that Cipher in its current form is too good for 3 and too weak for 4. You could change the card, price it in debt or Potion or price it at 4 and add an on-gain bonus.
I view Cipher like Diplomat. Diplomat is only +2 cards if you don't set up its bonus. It still costs 4 whether the set can trigger that bonus or not.
Cipher is similar. It's better than +2 cards, and if you can trigger the bonus (even some of the time), it's quite useful.
With Smithy you want about 1 Village per Smithy, so you're buying Village - Smithy each time. An average cost of 3.5 coin per card.
With Cipher you want about 1.5 Villages per Cipher, so you're alternating between buying Village - Cipher and Village - Village - Cipher. An average of 3.4 coin per card.
If you really want to always combo your Cipher, you'll want Village - Village - Cipher, costing 3.33 coin per card.
A fully optimized Village-Smithy Village-Smithy Village-Smithy play is equivalent to 6 Labs (+12 cards, +1 Action.)
A fully optimized Village-Village-Cipher Village-Village-Cipher is strictly better than 6 Labs (You draw 16 cards, topdeck/discard 4, +1 Action), cheaper per card, uses the same amount of cards, but is slightly harder to setup (the order matters more, but you're going to have more Villages in your deck, so it's not as hard as it seems.)
Both setups equally leave +1 action left for your other cards. Cipher, however, is flexible. In a pinch, you can use fewer of your actions and get fewer cards and still get some value.
It may seem like Cipher only nets you 2 cards each time you play it, but the option to play Cipher again is like having another Cipher in your hand, so there's actually a hidden "third card" when you play it the first time. Plus it lets you topdeck collided terminals.
Overall, I'd say that Cipher isn't any better or worse than Smithy, it just plays differently and is higher variance. In many cases (no trashing/high greening/discarding doesn't matter as much), it's much better. In many cases (no Villages), it's much weaker.
Edit: Fixed some miscalculations.