This is an attempt to wrap up the character of Walter Mashburn. So I've posted quite a bit about Mashburn, but I think I can tie a few more pieces of his personality to Red John, so here I go. Typically when a person rapidly acquires wealth (as Mashburn did) they enter a new type of social class called Nouveau Riche, meaning new rich. This social class is basically rich people who don't know how to behave, they lack manners, they aren't cultured, they are too gaudy, etc. They are frowned upon by their "superiors," the old rich. The old rich have etiquette, "modesty," and are cultured. Sometimes people who have recently acquired wealth find themselves alone and socially ostracized (most of this from http://www.wisegeek.com/who-are-the-nouveau-riche.htm). So, one who sought to rise above the Nouveau Riche class into the old rich class must learn quickly and have several "debuts." 

Some things to note about Mashburn, he is a member at the Catamaran Club in Marin County. This club is obviously for the very wealthy, otherwise Mashburn wouldn't attend this private club. Furthermore, the club is sharply contrasted from a Nouveau Riche club in that it isn't gaudy (http://www.dba-oracle.com/golf_travel/joining_a_country_club.htm). If you notice, the people around Mashburn (as he eats with Jane and Lisbon) are a slightly old couple (latter middle age). They both have wrinkles and are dressed in a sweater vest (the man) and a sweater tied around by the arms (the woman). Very old moneyesque. Furthermore, Mashburn himself doesn't dress in a show-off manner. A blazer not matching his slacks, with a vertically striped button down. Mashburn also has a recognition for art, as he bought Liselle a very expensive painting to reward her for finding him a rare car. He propositioned her for sex, but his gift was a painting, not jewelry or something fancy that you might think a rich guy would give a girl he's interested in. Very peculiar in my opinion. In "red hot," Mashburn throws a party around other people that don't dress is a gaudy fashion (far from social ostracism) that don't appear to be part of the new rich. (A little note: the new rich typically give to charity as a means to ascend from their "lowly" status as the new rich [as mashburn does].)

So, Mashburn (in my opinion) has demonstrated that he has quickly moved out of the nouveau riche class, which is quite a social feat without having the ancestry. One might think of the things he had to do to move from reform school student to socially accepted billionaire: acquire culture, etiquette, and dress "fashionably." The first two entail a good amount of education. Learning the classics (like Bach), poetry (like William Blake), and how to decipher quality art (like the painting he gave Liselle) would seemingly be good ways to culture one's self. 

In summary, Mashburn's quick rise to socially accepted billionaire was probably not just a result of his money (given the way social classes work), but rather his money and personal effort to integrate (which makes perfect sense giving his level of ambition). His personal effort probably included cultural education (literature, art, history, poetry, music, etc.), which accounts for RJ's enjoyment of Bach and his recitation of William Blake.