I'm not sure that your example to the right is in single stroke, but there definitely are examples where the single stroke is certain. E.g. here (76r line 9):
the n is single-stroke (the s is double-stroke).
On the other hand, there are examples when two strokes are literally disjoint, e.g. 66v line 11:
Maybe, as Rene says, this is the result of a particular writing technique. In this case, two strokes would not mean "two passes", but just a convenient way of performing the only pass. The fact that b-shapes do not exhibit two-stroke behaviour would then be explained by that they do not have the salient point (the point where the quill "changes direction").
About the tail coverage, it definitely waits statistical approaches, although I'm not sure what's the appropriate way to approach it. Simple counts won't tell us much - whatever the distribution, it always can be written off to the writing habits. Perhaps, it makes sense to pick some more or less frequent vord with a tail n (luckily, daiin, as the most frequent vord, presents itself as a perfect candidate), an then see if vord combinations featuring this vord do exhibit any correlation with the tail coverage of n. Say, if vord X is frequently found before daiin with no tail coverage, while vord Y is frequently found before daiin with double coverage, that would look interesting, suggesting that the two daiins stand for two different words.
the n is single-stroke (the s is double-stroke).
On the other hand, there are examples when two strokes are literally disjoint, e.g. 66v line 11:
Maybe, as Rene says, this is the result of a particular writing technique. In this case, two strokes would not mean "two passes", but just a convenient way of performing the only pass. The fact that b-shapes do not exhibit two-stroke behaviour would then be explained by that they do not have the salient point (the point where the quill "changes direction").
About the tail coverage, it definitely waits statistical approaches, although I'm not sure what's the appropriate way to approach it. Simple counts won't tell us much - whatever the distribution, it always can be written off to the writing habits. Perhaps, it makes sense to pick some more or less frequent vord with a tail n (luckily, daiin, as the most frequent vord, presents itself as a perfect candidate), an then see if vord combinations featuring this vord do exhibit any correlation with the tail coverage of n. Say, if vord X is frequently found before daiin with no tail coverage, while vord Y is frequently found before daiin with double coverage, that would look interesting, suggesting that the two daiins stand for two different words.