Several linguistics-oriented scholars, most notably Dr Mair, have recently noted the growing trend in written Chinese discourse towards "digraphia" - the dual use of Pinyin and Chinese characters as sort of a protomorphic kanji+katakana-esque ensemble.
The obvious, and de-facto standard, explanation for this growing phenomenon is the difficulty of writing/remembering characters such as 喷嚏 relative to the simplicity of writing "pen ti". However I am curious concerning phenomena such as the following (from the package of a present sent to someone around CNY):
Where "xin1 yi4" is the pinyin for 心意 - incredibly basic characters for which the "too difficult" explanation simply doesn't apply.
So what is going on here? How is the Pinyin+Character combination perceived by native Chinese speakers? Is the inclusion of pinyin a stab at some sort of additional sophistication somehow conveyed by the inclusion of roman letters? Is it an aesthetic effect (e.g.: it makes for an "interesting mix")?
How should 老外 interpret the "effect" of such combinations of Pinyin and characters?