Heads you win, tails I lose

When thinking about subjects like the fine-tuning argument it becomes apparent that the theist loves to have their cake and eat it. They thrive off a “heads I win, tails you lose" scenario.

What I mean by this can be exemplified as follows:

In the fine-tuning argument when a sceptic argues:

The universe is more fine-tuned for death than life.

The size of the universe is so unbelievably and unnecessarily massive that it appears that it is not designed for human life.

Etc etc

the theist retorts:

The fine balance of these constants means that it is just about right for life. Anything more or less will not permit life. Aah, but size does not matter. Just because life might just exist in one corner of the universe does not necessarily mean that the universe is not designed with us in mind. The value of the diamond is not particularly size dependent.
And so on.

While on the surface these retorts may seem logically coherent, the scenario that they build up is problematic. The end result is this:

If the universe had been much smaller, just right for human life on a human scale, then the universe would have been obviously designed for humans, so would claim the same theist. The universe is the direct opposite of that, but still this somehow shows that God obviously designed it, such as the design being based on other purposes, using the analogy of the Sistine Chapel (one marvels at the size and beauty of it but it doesn’t need to be that big; that the awe and wonder derives from its magnitude) and so on.

If the universe had constants that were comfortably in the middle of a range of values that supported life, and if the universe wasn’t so incredibly unfriendly to life and downright deadly, then the theist would argue that voilĂ , the universe is designed for life.

So both ends of the spectrum- a deadly universe and a life-friendly one (and everywhere in the middle) – the theist claims (or would claim) that this is evidence for a designer-creator god!

Likewise, with regards to abiogenesis (the creation of life in the universe), the theist presently claims, in the absence of totally conclusive evidence, that God must have supernaturally done his stuff to create life. However, if we now found conclusive empirical proof that abiogenesis was naturalistic in mechanism, then the theist would simply switch from supernatural mechanism to saying something akin to "God obviously had to create the natural laws and mechanisms to bring about life" which is exactly what theistic evolutionists maintain.

This isn’t just the case for the fine-tuning arguments, but also in biblical criticism where the ad hoc nature of the contrived defences of biblical authority and historicity mean that, with incredible historical issues and incongruities within the same text and with extrabibilical texts, the issues and respective defences still show that the bible is authoritative and true. However, if these issues didn’t exist, the theist would claim, still (and possibly more), that the bible were true and accurate.

Heads you win, tails I lose.

The ramifications of this approach are clear. There is no scenario that could exist which would prove, even probabilistically, that God did not exist or design the universe or whatever. No matter what scenario, the theist would contrive some explanation as to why that scenario supported the existence of God.

What examples can you think of where theists employ this kind of reasoning?

[Update: also as a video for those too lazy to read:]