Karsh presents a wealth of new information on Zionist-Arab-British geopolitics,as well as what was going on among Palestinians in 1948. But his boast of having refuted the New Historians is premature.
Take his account of 1948. Karsh offers nothing to support his claim that there were only a few expulsions--and it needs support,considering that over a hundred expulsions are recorded in Israeli archives. He deals with Arab and Jewish terrorism,but leaves out most of the massacres of Arabs by Israeli infantry,and even expresses skepticism about the Deir Yassin massacre. He records the Israeli offers at Lausanne,but omits the initiatives by Egypt and Syria(first uncovered, I think, by Simha Flapan). He also makes it sound as though Ben-Gurion's offer to take back 100,000 refugees was unconditional,which it wasn't.
Karsh's insistence that there was no conflict between Zionism and Arab interests strikes me as naive. He constantly quotes Zionist statements about coexistence,but doesn't see the inconsistency between this and a Palestine "as Jewish as England is English". The statements of Herzl, Ben-Gurion and others about transfer are left out, as is the eviction of Arab peasants and shepherds.
There are little errors, such as his claim that the Zionists accepted the Peel partition plan---the World Zionist Congress rejected it(cf. Christopher Sykes, Crossroads to Israel). Sometimes,when he differs with a New Historian they both cite contemporary sources, so we have no basis,beyond our prejudices, for choosing.
The quote of Palestine as "Jewish as England is English" was from Chaim Weizmann, testifying before the Peel Commission in November 1936. Here is the Palestine Post article that mentions it:
In that same testimony, however, Weizmann emphasizes both his hopes for Arab-Jewish cooperation as well as the frustrations Jews had in being discriminated against by the Arabs and his feelings that the Arabs were treated badly - by Great Britain! (click to enlarge)
From my own readings of contemporaneous Jewish Palestinian sources, it is clear to me that the quotes about "transfer" and other quotes that indicate bigotry against Arabs by the Jewish leadership have been taken out of context (not to mention the many that are wholly fiction.) Here is just one example - Weizmann spoke about Arabs at length to the Commission, yet only one sentence makes it into the "New Historians' " books. Karsh contextualizes it more accurately while the "New Historians" emphasize only the anti-Arab sounding statements and ignore the far more numerous ones that indicate sympathy and the desire for cooperation. Whether Karsh goes to far in the other direction is an open question, but his viewpoint is clearly ignored by the revisionists.
As far as how the Jews responded to the Peel Commission recommendations, it appears that the Zionist Executive of the WZO accepted it in theory but rejected the specific borders and they were charged with further negotiations concerning the matter. The absolute Arab rejection made that point moot.