I'm no seminar historian, so I'm largely following wiki on their process.
The voting went as follows:
Jesus undoubtedly said this or something very like it.
Jesus probably said something like this.
Jesus did not say this, but the ideas contained in it are close to his own.
Jesus did not say this; it represents the perspective or content of a later or different tradition.
(The five Gospels : the search for the authentic words of Jesus : new translation and commentary p36-37)
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Take the Beatitudes of Matthew 5:3-12:
Congratulations to the poor in spirit!
Heaven’s domain belongs to them.
Congratulations to those who grieve!
They will be consoled.
Congratulations to the gentle!
They will inherit the earth.
Congratulations to those who hunger and thirst for justice!
They will have a feast.
Congratulations to the merciful!
They will receive mercy.
Congratulations to those with undefiled hearts!
They will see God.
Congratulations to those who work for peace!
They will be known as God's children.
Congratulations to those who have suffered persecution for the sake of justice!
Heaven's domain belongs to them.
Congratulations to you when they denounce you and persecute you and spread malicious gossip about you because of me. Rejoice and be glad Your compensation is great in heaven, Recall that this is how they persecuted the prophets who preceded you.”
Of the nine 'congratulations' here, none are certain, only three as probable, the last two as not His words, but based on His ideas, and the other four He did definitely not say ... and quite how the Seminar arrived at 'congratulations' ...
The commentary (p139) says:
"Congratulations! In these so-called beatitudes (my emphasis – they're not 'blessings' in the eye of the Seminar), Jesus declares that certain groups are in God’s special favor. “Blessed” is an archaic way of expressing that idea. The Scholars Version has replaced the traditional term, derived from Latin, (the Latin derived from the Greek) with its modern equivalent: “Congratulations!”"
The translation note “Congratulations/Damn” in the “Dictionary of Terms and Sources” (p543) expands these remarks.
"Congratulations replaces the archaic term “Blessed,” and the more recent but less appropriate terms “happy” and “fortunate” in Scholars Version. Jesus declares the poor to be possessors of God's domain. For that, speakers of English would say “Congratulations” "
I don't think the English would, not if they meant to imply Divine favour – the term "blessed" derives from the Greek μακάριοι, makarios, and translates as 'blessed,' 'happy,' 'fortunate,' 'prosperous,' but originally with a connotation of divine or heavenly bliss. Strong's Concordance has: "μακάριοι makarios, from mak-, 'become long, large' – properly, when God extends His benefits (the advantages He confers); blessed."
Clearly 'congratulations' does not infer God's favour... so a radical departure from the original text.
The commentary reads:
"Matthew's versions of the poor, weeping, and hungry sayings were designated pink, rather than red, because the reasons for congratulations, in two instances, have already been interpreted as referring to religious virtues rather than to social and economic conditions."
(The Seminar dismisses Jesus speaking in terms of 'spiritual virtue'.)
"Sayings about real poverty and actual hunger are more likely to have been “spiritualized” by the community than aphorisms about virtue turned back into distressed circumstance."
(Here the assertion that Jesus was not a spiritual teacher?)
"Into the list he inherited, Matthew introduces four congratulations not found in either Luke (Q) or Thomas. To commend the meek, the merciful, those with undefiled hearts, and those who work for peace is quite different from congratulating the poor, the hungry, and the weeping.
(So Jesus never said this at all?)
"These additional beatitudes offer reward for virtue rather than relief from distress. People normally expect virtue to be rewarded; and the virtues in question are well known and widely accepted among Judeans of the period. There is no surprise, no reversal, no paradox. In sum, these sayings are not characteristic of Jesus."
(So Jesus must speak in terms of surprise, reversal, paradox, to be considered genuine. We can see the Seminar's Jesus as first and foremost, a sociological, rather than a spiritual, voice.)
"Further, Matt 5:5 is simply a paraphrase of Ps 37:11; Matt 5:8 is based on Ps 24:3-6. There are numerous precedents for the commendation of those who are agents of mercy or peace. Matthew has amplified the list by borrowing common lore and putting it on the lips of Jesus."
(No chance then that Jesus might also be well versed in the Hebrew Scriptures and was using them Himself?)
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Following on in Matthew, we have this famous 'Salt of the Earth' discourse (p139):
"You are the salt of the earth. But if salt loses its zing, how will it be made salty? It then has no further use than to be thrown out and stomped on. You are the light of the world. A city sitting on top of a mountain can't be concealed. Nor do people light a lamp and put it under a bushel basket but on a lampstand, where it sheds light for everyone in the house. That's how your light is to shine in the presence of others, so they can see your good deeds and acclaim your Father in the heavens.”
Commentary:
"The first salt saying is Matthew’s creation; he has remodeled a simple saying about salt that has lost its saltiness (Mark 9:50a/Luke 14:34-35) into a saying about Christian presence in the world. The saying as it now stands commends Christians as the salt of the earth and thus reflects the social outlook of the later community. As a parallel to “You are the salt of the earth,” Matthew has created the saying in 5:14a: “You are the light of the world.” Jesus himself rejected insider/outsider discriminations of this sort: he included outsiders such as sinners and toll collectors, along with other “undesirables,” among his companions. As a consequence, the Fellows of the Jesus Seminar designated Matt 5:13a black.
It goes on in the same vein, stripping out all spiritual assertion or implication, in favour of a 'social outlook' ... it seems to me that once you strip out text as they do, what's left is pretty bland?
It's hard to see why His followers gave their lives for such an anodyne message?
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The views of the Seminar were shaped by the 'extreme' liberal views of its founders. I say 'extreme' because the position was so left-field as to be the opposite pole of extreme right-wing conservative Christianity – and I can appreciate theirs was a reaction to exactly that, and that's no bad thing, if we look at where Conservative Christianity in the US stands today.
But many liberal scholars distanced themselves from the Seminar – and the Seminar did itself a disservice by courting publicity. had it stayed within the campus world of scholarship, there might have been convivial debate – N.T. Wright, who is notably critical of the Seminar, is a close friend of one of its members. Others, Crossan and the like, have debated their position in scholarly circles without the hoo-ha.
And for balance, David Bentley Hart says much the Seminar would delight in, regarding Jesus' sociology, but Hart's Jesus is nonetheless a spiritual figure, the Son of God, whereas the Seminar as a body is anti-spiritual, anti-mystical – there were no miracles, there was no Transfiguration, no Resurrection, and so on.
In the end, 80% of the Gospels are rejected as inauthentic. 80%.
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Inevitably, and inescapably, the Seminar rejects those materials they see as "nontypical" of Jesus – not on the basis of external evidence – but on their own image of what He surely must have been – a sociopolitical prophet who happens to mirror the liberal concerns of the last quarter of the 20th century ...
... Yes, these are the texts one can reliably accept as being said by Jesus.
This is the third time you have politely and discreetly corrected my errors (the 2nd was the plural feminine Elohim – 
