Interesting. Sort of an odd off-shoot of the Aghora tradition in India... practitioners rub the ash of dead folks on their bodies or sit on bones while they meditate in the areas where cremation has occurred. Perhaps to quell desire but mainly to place their own mortality at the forefront of their awareness.
Religions such as Christianity and Islam are certainly much more devotional than scientific. As are aspects of Mahayana Bhuddism, and Bhakti/Karma Yoga. But certainly Raja Yoga, Hatha Yoga, and Vajrayana Bhuddism would be examples of spiritual sciences in that you can sit down and personally explore the tradition in an empirical way (via meditation, pranayama, asana,...). And people have been doing so for thousands of years. As a good scientist you cannot negate these practices. You can only say you have not done the experimentation necessary to replicate them yourself.
>> What I have always found interesting about Godel was his statement
>>that any system contains true statements which cannot be proven
>>true within that system. <<<
But supposedly can be "proven" in other systems. Hence, Yogi's change their own system in order to probe for themselves literally what a Guru or spiritual book tells them. Christ it has been said was a Yogi who did this. His followers typically do not and so devote themselves to truths which they cannot or will not themselves probe (or disprove!) directly (it could be said that blocks to direct experimentation have been embedded in the Christian creed by Irenaeus, the council of Nicaea, the Catholic Church, and other historical entities).
On the other hand, science becomes devotional when it's practitioners forget that science can only probe and not prove anything. Scientific truth is provisional in that at any moment it's truths can be disproven by new experimental method. Saying that other domains of human experience do not exist is just bad science; a devotion to one particular human domain or system of experience over all others.
James
"If willing changes the world, it can only change the limits of the world, not the facts; not the things that can be expressed in language. In brief, the world must become quite another. It must so to speak wax or wane as a whole." [Wittgenstein, TLP, 6.43]