The subject of the memo is Nixon's concern that the public didn't view him as a "warm" human being. This, in Nixon's view, was extremely unfair. For example, it ignored his kindness in calling sick people "even though they no longer mean anything to anybody." Moreover, Nixon complained, he didn't get credit for not treating his staff and cabinet members like "dirt under my feet." "No President could have done more than I have done in this respect," he boasted. Nixon whined that the press was ignoring "innumerable examples of warm items -the way we have gone far beyond any previous President in this century in breaking our backs to be nicey-nice to the Cabinet, staff, the Congress, etc,, around Christmastime." After listing these and other "innumerable examples" of his (or rather "our") good deeds, Nixon was careful to note that "one of the great factors that should be emphasized is that the President does not brag about the good things he does for people." (emphasis in the original). It's worth noting that Nixon uses the royal "we" to refer to himself throughout most of the memo.
However, the memo is not entirely unintentional self-parody. A few of the things Nixon said are scarily accurate. Nixon's desire to create an image of warmth to complement his reputation for "efficiency" was the result of his realization that "effeciency and competence have precious little effect in determining whether Presidents are re-elected" (pg. 1 of the memo). Presidents who want to stay in office, Nixon explained, must also create a positive "mystique" about their personality. This statement is an exaggeration, but has important elements of truth. Indeed, Nixon's own landslide reelection in 1972 despite the disastrous nature of his policies (detente, wage and price controls, policies that helped cause eventual defeat in the Vietnam War, proposing massive expansions of the welfare state that even a liberal Democratic Congress thought unwise enough to reject) is Exhibit A in the argument that good policy is often not the best way to win and hold on to political office.
And, though Nixon never quite succeeded in fooling the public into believing he was a "warm" human being, he did successfully pose as an opponent of racial preferences, while actually establishing the first large-scale affirmative action programs (which angry white voters blamed on the Democrats, as Nixon had intended). He also succeeded in portraying himself as a conservative despite pursuing the most liberal policy agenda of any post-World War II president (on both of these points, see historian Joan Hoff's book Nixon Reconsidered; on affirmative action see also Hugh Davis Graham's excellent book. Ironically, Nixon found it easier to deceive people about the nature and consequences of his policies than about his personal "warmth."
UPDATE: I have corrected some poor phrasing that made it seem as if I meant to say that the Vietnam War was already lost by November 1972. It was not, but Nixon's policies on the War had by then helped put us in a position where eventual defeat was highly likely.
UPDATE #2: To further clarify, my argument is not necessarily that Nixon was worse than Democratic candidate George McGovern in 1972, though it is far from obvious that he was better. Rather, my claim is that Nixon and others had succeeded in persuading the public into supporting a disastrous set of policies that, by 1972, were embraced by the nominees of both parties. The options before the public in 1972 were both deeply flawed. But that fact itself was in considerable part caused by successful manipulation of political ignorance during previous years.
UPDATE #3: Having thought about this post some more, I think the last part of it goes too far in attributing Nixon's political victories too exclusively to political ignorance. The situation during the Nixon era was more complex than that, too complex to try to analyze in a small part of a blog post. I still think, as Graham and other scholars have documented, that Nixon did try hard to manipulate ignorance and met with some success. And I still believe that Nixon's policies were severely flawed - probably more so than those of any other post-WWII president. However, the Nixon record is too complicated to attribute primarily to one cause, and definitely too complicated to deal with in a short fragment of a blog post.