In a recent publication Dylan Winter introduced the concept of Poly Navicular Morbus (PNM),[ref] a condition that compels patients to acquire an increasing number of sailing craft. Here, we discuss the possibility that PNM maybe a sub-set of the Protracting Hull Syndrome (PHS), a poorly understood condition that leads to the acquisition of longer and longer boats.
Epidemiology of PHS and PNM
The major danger of PHS is that it is widespread but rarely diagnosed, and often considered benign, even normal. Popular wisdom has it that men (PHS, like PNM, affects almost exclusively males)[ref] should own a craft as long in feet as their age in years.[ref] That thought is flattering for this author: according to this rule he would be a 19 year young man.
In the wake of the recent economic crisis, the PHS pandemic was further masked by the response of the patients. While there were some cases of "downsizing" (see Figure 1), most subjects suffered an exacerbation of their PHS condition (Figure 2), a fact well evidenced by the increase in sales of luxury yachts.[ref]
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| Figure 1: A severe case of downsizing. (Note added on proof: In fact the gentleman is the late Charles Stock, who never owned a boat longer than his Shoal Waters and is a role model for all small boat sailors.) |
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| Figure 2: The paradoxic consequences of the economical crisis. After being afflicted by downsizing, this patient admires the new boat of his nephew, who suffered acute PHS. |
Conclusions
In view of the evidence presented Poly Navicular Morbus should be classified as a sub-set of Protracting Hull Syndrome. While PHS is widespread or even pandemic, PNM appears to be a special case afflicting middle-aged men.
