Gospel Intertextuality in Revelation

I've blogged about this previously and it still haunts me as a question that I've not heard anyone tackle: What would it take to demonstrate that a NT writer used a gospel and not just oral tradition?

If we assume for a moment that "Q" existed [I don't think it did, as demonstrated by Goodacre, et. al.]. But if this supposed document was available to be used by both Matt & Luke, what's to say that it could not have been used by other NT writers? Pushing this idea further, what's to say that other NT writers didn't have access to a gospel work? Is our presumption of a late date for the gospels a deterrent in exploring this idea? Why is the assumption always merely 'oral tradition'? Has anyone done a PhD on this?

Looking at Revelation, Graham Stanton notes that:

Revelation contains a handful of clear allusions to Jesus traditions. The following passages are among the most striking: Revelation 1:3, "blessed are those who hear and who keep what is written in it [the words of the prophecy]; for the time is near" (cf. Lk 11:28); Revelation 1:7, with its conflation of Daniel 7:13 and Zechariah 12:10, is closely related to Mt 24:30. In Revelation 3:3 (and cf. Rev 16:15) the Parousia of Christ is likened to the coming of a thief, as in the Q tradition (Mt 24:42–23 par. Lk 12:39–40). A Q tradition (Mt 10:32 par. Lk 12:8) also lies behind Revelation 3:5: "I will confess your name before my Father and before his angels." Revelation 13:10, "if you kill with the sword, with the sword you must be killed," is dependent on the Jesus tradition in Matthew 26:52. Most intriguing of all is the use in Revelation of the "hearing formula," "let anyone with ears to hear, listen," which is found in several strands of the Synoptic tradition (Mk 4:9 par. Mt 13:9 par. Lk 8:8; Mk 4:23; Mt 11:15; Mt 13:43; Lk 14:35). [Stanton, Jesus Traditions, DLNTD]

We know that there is some relationship between Johannine literature and the Revelation, but what about the synoptics? I've heard that Bauckham has explored "echoes" of the Jesus tradition in James, [see also R. E. Brown's table on Matt 5-7 in James] does his The Climax of Prophecy explore gospel traditions in Revelation? [My copy only arrives next week] Furthermore, if the author of Revelation uses the Hebrew scriptures but doesn't cite them explicitly, what's to say that he hasn't done the same with a gospel?

Finally, if one does demonstrate the probability of Revelation using a gospel [other than John?] does this validate Bauckham's thesis that the gospels were meant for a wider audience? Or would it suggest that they just circulated wider than there intended community? [My thinking suggests the latter but the former seems more interesting.] [Maybe a kind NT lecturer from Dingwall could email me his article on the Markan Community hypothesis so that I could explore this further? Hint, hint - nudge, nudge - wink, wink.]

Are these musings completely off the wall?