On careful reading of the link, I can not find any support for the claim that he sometimes used a capitalized version of his name. If he did normally capitalize, and only used the lowercased version in artistic contexts, that would certainly give credence to your idea. But the link does not give any support for this.
Quoting from http://faculty.gvsu.edu/websterm/cummings/caps2.html :
> As we may have mentioned, due to the kindness of D. Jon Grossman's son, Jerome, we have the complete file of Jon's correspondence with Cummings. On making a preliminary tour through these letters, we found Jon preparing a French edition of his translations of Cummings' poetry, and on 27 February 1951 he wrote to the poet: "are you E.E.Cummings, ee cummings, or what?(so far as the title page is concerned)wd u like title page all in lowercase?"
> The poet replied on 1 March 1951: "E.E.Cummings, unless your printer prefers E. E. Cummings/ titlepage up to you;but may it not be tricksy svp[.]"
> That seems definitive to us: may it not be tricksy!