Comments regarding the NFCTag interface

Hello everyone,

I have a quite small, but potentially important comment regarding the
NFCTag (http://www.w3.org/TR/2014/WD-nfc-20140114/#nfctag-interface)
interface. In the current draft it only supports reading and writing to an
Ndef tags. In similar implementations, such as the Android API, it usually
also possible to communicate with a tag on a lower level (typically the
ISO/IEC 14443-4). Please refer to  the following method in the Android
API:s for an example:
http://developer.android.com/reference/android/nfc/tech/IsoDep.html#transceive%28byte[]%29

Typically such an interface allows sending and receiving APDU:s to a tag
not only implementing Ndef but also other applications such as OTP, OpenPGP
or even payments via Visa or MasterCard. In the terminology used in the
current draft such an method would look something like this:

Promise transceive(byte [] command);

The Promise would also contain a byte array (byte[]) which would be the
corresponding response APDU. This could either be included in the NFCTag
interface or in it's own ISOTag or similar interface. I believe such an
interface/method would be immensely useful while at the same time being
very easy to implement since similar functionality is required internally
to implement the Ndef messaging.

Has such a method already been discussed and discarded or do you think such
a method could indeed add something to the API?

Best regards,
Petter