I haven't read a lot of Batchelor, so maybe it is unfair of me even to comment. My sense is that the 'secular Buddhists' are guilty, at the end of the day, of cherry picking. While Batchelor's focus on the secular teachings of Gautama may be accurate to a degree, Batchelor simply leaves out the teachings of anatta, kamma, and punabbhava because they involve, in Batchelor's view, religion or matters of faith. To my mind, as these teachings were integral to the Buddha's Dhamma, they are integral and necessary if one is to study or practice what we call "Buddhism." If Batchelor wishes to strip away key aspects of the Dhamma, he is free to do so, but I object to his use of the term 'secular Buddhism.' As a scholar pointed out recently regarding the secular Buddhism movement (I think it was a recent Tricycle article), you can't be partially pregnant....
In A Secular Buddhism
, Batchelor acknowledges that a traditional, literal reading of the four noble truths as found in SN 56.11 "would seem to leave little if any room for a secular interpretation of the text." So in order to make the four noble truths fit his secularization project, he employs a number of interpretive maneuvers.
First, he calls into question the content of the sutta by relying on the methods of textual criticism. To do this he refers to Norman's philological analysis of SN 56.11, where Norman concludes that "the earliest form of this sutta did not include the word ariya-saccaṃ (noble truth)." Batchelor characterizes this as a "startling conclusion." And apparently, for Batchelor, this philological detail is sufficient evidence for him to rewrite the sutta in a fashion that's more to his liking.
One of the implications that Batchelor wants to draw from this philological analysis is that "the Buddha may not have been concerned with questions of 'truth' at all." However, there are other suttas in the Pāli Nikāyas which the terms "noble" and "truth" are either integral to the discourse itself, or implied by the discourse. For example, in the same Saccasaṃyutta SN 56.28 states:
Bhikkhus, there are these four noble truths.... In this world ... the Tathāgata is the noble one. Therefore, they are called noble truths.
This correlation between the Buddha as the "noble one" and the "noble truths" wouldn't have any meaning if one were to take the qualification "noble" out of the discourse. Another example, this time pertaining to the qualification of "truths," can be found in SN 56.27:
These four noble truths, bhikkhus, are actual, unerring, not otherwise. Therefore, they are called noble truths.
Norman himself thought that this qualification of the noble truths as avitathāni anaññathāni "would seem … to be the reason why they are called 'truths.'"
The four noble truths are merely theoretical statements apart from the minds that realize them. Thus, it's entirely appropriate to say that they are unerring truths
to be known by unmistaken cognitions. But according to Batchelor, considering them to be truths was a significant part of the degeneration of the ancient Buddhist traditions, transforming the teachings "from a liberative praxis of awakening into the religious belief system called Buddhism."
Batchelor also takes issue with the traditional comparison of the four noble truths to the medical diagnosis of an illness, which he considers to be a later "strained commentarial device with authoritarian undertones, introduced to justify the incongruous ordering of the propositional 'truths.'" However, there is a sutta from the Saṃyukta-āgama (T 99) extant in Chinese translation that takes as its theme exactly this comparison of the noble truths to a medical diagnosis. And according to Ven. Anālayo, in Right View and the Scheme of the Four Truths in Early Buddhism
[V]ersions of this discourse can be found in another Saṃyukta-āgama (T 100) that has been partially preserved in Chinese translation, in another discourse preserved as an individual translation in Chinese, in a discourse preserved in Uighur fragments, as a sūtra quotation in Śamathadeva's repertory of canonical quotations in the Abhidharmakośabhāṣya preserved in Tibetan, as a partial sūtra quotation in the Abhidharmakośavyākhya, and as a partial sūtra quotation in the commentary on the Arthaviniścaya-sūtra.
Just because a discourse isn't extant in the Pāli Nikāyas doesn't necessarily mean that it's any less ancient than those that are in the Pāli collections. Indeed, even Buddhaghosa, the author of the Visuddhimagga, knew of this medical diagnosis comparison to the four noble truths, and he was primarily relying on Pāli textual transmissions. So there's little reason to conclude that this diagnostic metaphor was "introduced to justify the incongruous ordering of the propositional 'truths'" as Batchelor suggests, just because it's no longer extant in the Pāli Nikāyas.