Was Buddhism during the life of the Buddha unique in the history of religion per Huston Smith? In chapter 3 of Buddhism, A Concise Introduction, Huston Smith and Philip Novak give a list of characteristics present in Hinduism at the time of the Buddha:


Authority: "talent and sustained attention will lift some people above others in matters of spirit"
Ritual
Speculation: "Whence do we come, whither do we go, why are we here? People want answers to these questions."
Tradition
Grace: "In the last resort the universe is friendly; we can feel at home in it."
Mystery: "Being finite, the human mind cannot begin to fathom the Infinite, which it is drawn to."


The authors described Buddhism as "(at the start) a religion almost entirely devoid of each of the above mentioned ingredients without which we would suppose that religion could not take root."

In particular, "Buddha preached a religion that skirted speculation." The authors quote from Sutta 63 of the Majjhima Nikāya, wherein one of the Buddha's disciples says,


  Whether the world is eternal or not eternal, whether the world is finite or not, whether the soul is the same as the body or whether the soul is one thing and the body another, whether a Buddha exists after death or does not exist after death—these things the Lord does not explain to me.


Near the end of the chapter Smith and Novak write,


  After his death all the accoutrements the Buddha labored to protect his religion from came tumbling into it, but as long as he lived, he kept them at bay. As a consequence, original Buddhism presents us with a version of religion that is unique and therefore historically invaluable


This is how Buddhism is often presented in the west, but my impression was that there were no extant texts to support it. For example, via Wikipedia, here is a seemingly contradictory claim from Andrew Skilton's A Concise History of Buddhism.


  It is important to stress that, despite modern Theravada teachings to the contrary (often a sop to skeptical Western pupils), [the Buddha] was never seen as being merely human. For instance, he is often described as having the thirty-two major and eighty minor marks or signs of a mahāpuruṣa, "superman"; the Buddha himself denied that he was either a man or a god; and in the Mahāparinibbāna Sutta he states that he could live for an aeon were he asked to do so.


The Mahāparinibbāna Sutta is part of the Pāli Canon so AFAIK is as old as any record we have. Is Huston and Novak's view at odds with Skilton's? Or am I missing something? And if they are at odds, can Huston and Novak's view be supported?
To remedy this apparent discontinuity, I think it is wise to look at how the Buddha taught and what methods we proposed to attaining peace. If he were to propose a viewpoint that focused on the pragmatic path and not the esoteric, that would leave one to believe that there is no points at odds. That is not to say that there is not a Buddhist phenomenology or ontology, but that the Buddha did not propose the investigation as a proper means of attainment.



Regarding the Sutta mentioned by Andrew Skilton: 


  Kappam va tittheyya kappavasesam va. Comy. takes kappa not as "world-period" or "aeon," but as ayu-kappa, "life span," and explains avasesa (usually "remainder") by "in excess."
  
  Comy.: "He may stay alive completing the life span pertaining to men at the given time. (Sub. Comy.: the maximum life span.) Kappavasesa: 'in excess' (atireka), i.e., more or less above the hundred years said to be the normally highest life expectation."
  
  Among the numerous meanings of the word kappa, there is, in fact, that of time in general (kala) and not only the duration of an aeon; but the meaning "life span" seems to have been ascribed to it only in this passage. Also, the meaning "in excess" for avasesa (usually "remainder") is unusual.
  
  The four constituents of psychic power (iddhipada) are concentration due to zeal, energy, purity of mind, and investigation.



Access to Insight note on Mahāparinibbāna Sutta 




Now, let us look at how the Buddha taught and the overall focus of the teachings.

In the Alagaddūpama Sutta  (MN 22) the Buddha discusses views and will help in the search for your answer. It is much too long to summarize in the post, but it provides an underpinnings of the pragmatic aspects

The Dīghanakha Sutta is another sutta we can look at to see how the Buddha viewed esoteric fixed views:


  “There are these three kinds of feeling: a pleasant feeling, a painful feeling, and neither-pleasant-nor-painful feeling. On the occasion when one feels a pleasant feeling, one does not feel either a painful feeling or a neither-pleasant-nor-painful feeling. One feels only a pleasant feeling on that occasion. On the occasion when one feels a painful feeling, one does not feel either a pleasant feeling or a neither-pleasant-nor-painful feeling. One feels only a painful feeling on that occasion. On the occasion when one feels a neither-pleasant-nor-painful feeling, one does not feel either a pleasant feeling or a painful feeling. One feels only a neither-pleasant-nor-painful feeling on that occasion.
  
  “A pleasant feeling is inconstant, fabricated, dependently co-arisen, subject to ending, subject to vanishing, fading, ceasing. A painful feeling is also inconstant, fabricated, dependently co-arisen, subject to ending, subject to vanishing, fading, ceasing. A neither-pleasant-nor-painful feeling is also inconstant, fabricated, dependently co-arisen, subject to ending, subject to vanishing, fading, ceasing.


Here we see that the Buddha, focused on what we perceive rather than views about what we perceive. Earlier in the sutta, he discusses some Brahmans view with respect to please: All is pleasing to me, All is not pleasing to me, and 'A part of me is pleasing; a part of me is not pleasing'. The focus here is not a categorical answer of what is and is not pleasure, but how we relate to the pleasure and the nature of the pleasure.


  “Kassapa, the statement, ‘With the one who acts being the same as the one who experiences, existing from the beginning, pleasure &amp; pain are self-made’: This circles around eternalism [see Appendix Two]. And the statement, ‘With the one who acts being one thing, and the one who experiences being another, existing as the one struck by the feeling’: This circles around annihilationism. Avoiding these two extremes, the Tathāgata teaches the Dhamma via the middle: From ignorance as a requisite condition come fabrications…. From birth as a requisite condition, then aging-&amp;-death, sorrow, lamentation, pain, distress, &amp; despair come into play. Such is the origination of this entire mass of stress &amp; suffering.



Acela Sutta




The point I'm trying to make is that the Buddha was very thoughtful in how and why he answered questions. He focused on what led to the end of suffering, which was not focusing on the esoteric teachings (in most cases). We see time and time again that he speaks in terms of suffering and the cessation of suffering. Thus I conclude, that there is no disconnect between the two.

This is not a direct answer persay, but I hope this can spur further discussion

References:

Skill in Question: How the Buddha Taught by Thanissaro Bhikku

Buddhist Romanticism by Thanissaro Bhikku