Linked is a summary of a study to be published shortly that looks at the link between the way numbers are represented in the brain and how that can affect visual and haptic perception of length. In essence, focusing on a larger number changes perception of the length of something in the visual field or an object that is experienced haptically, running the hands across it in some manner. Many pronunciation systems use vowel numbers similar to those used in HICP, where the numbers roughly correlate with those on a the mirror image of a clock face--or the place in the standard IPA matrix. According to this research and other previous studies the effect should be to give the learner the felt sense that, for example, vowel #2 (high-front-lax) is perceptually shorter than vowel #1y (high-front-tense-unrounded + off-glide.) Acoustically, that is certainly the case. Whether a vowel #11 (high-back-lax-rounded) is perceptually longer than a vowel #2 (high-front-lax-unrounded) is an empirical question, although my guess is, to quote one of my favorite lines from Bertrand Russell, that "[That] difference that doesn't make a difference, doesn't make a difference . . . " What is of interest, however, is the potential effect of using digraphs such as 1y or 11w for diphthongs or vowel+off-glides, or using double numbers such as 22 or 66 for lax vowels that are lengthened before voiced consonants or sonorants--accompanied by haptic anchoring of course! The type of haptic anchoring used, whether a light tap or brush or scrape or plunging action may interact more with the numbers assigned to vowels than I had previously thought. It may be time to consider reframing the nature of the number system itself to correlate better with the visual and haptic felt sense of vowel length. We can at least wait until the research study is published--and then either mortgage the house to come up with the $32 to buy it or wait until it shows up someplace else as a PDF on some pirate's blog . . .