No particular reason other than the proximity of a new mark registration and a workpiece made so close to his presumed date of death. Of course he may have been run down by a sedan chair the day after assaying this, but he seems to be very active in 1740.
Grimwade only puts it forward as a probable after all
The only PCC will of a Samuel Hutton in the period, is that of Samuel Hutton, Gentleman of Saint Margaret Westminster , Middlesex Date 28 August 1752 , who is probably unconnected. . No London Huttons had a probate at PCC in 1739-1740, so it appears that Sarah's presumed husband may have died intestate. Which does indicate an unexpected death - usually at this period they made their wills very much in imminent expectation of dying .
I personally am very clary of drawing logical conclusions of this type ,as I've been caught ot several times by plausible co-incidences !
see
viewtopic.php?t=17482for another example.
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