Reading the Sutras is important at some point in the practice of a Buddhist, although there is something about them that we now understand which was not so well known even 100 years ago: Namely, none of them (and I mean
none of them) were actually "
written during the lifetime of the historical Buddha" (even the oldest that we have were not written down until several hundred years after his death, before which the tradition was passed from generation to generation orally). The teachings were passed down orally alone (which may or may not have been a sloppy process, with much corruption of the original), until somebody finally wrote them all down hundreds of years after he was dead ... and then all the Buddhists immediately set to disagreeing about which of them had the "
authentic" teachings, and exactly what they meant!
What is more, teachings evolved and developed in all schools (even the South Asian "Theravadan" traditions, which have the image of being "closer to the original" than the Northern Asian Mahayana traditions have themselves been evolving and developing for 2500 years, and
don't even agree among themselves on important details).
Nobody knows exactly what the original Buddha taught, not even the greatest Buddhist scholars, historians or monks. (I just finished a book by Bronkhurst (discussed here:
http://www.westernbuddhistreview.com/vo ... ation.html), one of the great Buddhist historians ... they can only guess.
What is more, the Mahayana traditions, of which China, Japan, Korea and much of Vietnam are part, including all the Zen schools (and don't even bring in Tibet and "Vajrayana Esoteric Buddhism"!), are a conscious break from the original flavor of Buddhism (with Sutras that are,
each and every one, the works of later authors who pretended that what they were writing were "the revealed words of the Buddha". Of course, they don't say that they are a conscious break, but rather that they are teaching the "real" teachings of the Buddha, who did not really mean (or considered to be "lesser" teachings) everything else attributed to him. In fact, they are each the works of writers (sometimes a mix of many writers), each with a particular philosophical view, who put words in the Buddha's mouth. In addition, commentators on these Sutras come in 1001 flavors, depending on who the commentator is (for example, the Heart Sutra can be read several different ways ... and has been).
In other words, anyone reading these Suttas/Sutras/Commentaries must be an educated reader about what they are reading, how it is translated, and what the philosophical bent of the true writer(s) was, and where that particular work fits in the complex universe of Buddhist writings. They can often (even within the same book) say things in complete disagreement, and from radically different philosophies of Buddhism.