There appear to be two variations on the "sailors' fashion" of shoes: one features one strap hanging loosely over the forward edge of the buckle frame. Illustrations seem to indicate that this was the more common style. The second style has the straps crossed and fed under the forward side of the buckle frame, as seen in "Watson and the Shark."
Here are some images of one of my own shoes, with the straps buckled and trained in various manners:
The buckle attached to the chape strap in the usual fashion:
The shoe buckled in the usual fashion:
The shoe buckled in the usual manner, but with the straps pulled forward:
The buckles installed on the chape strap in the conjectural “quick-release” fashion:
The tongue strap buckled:
The “quick-release” method, with both straps loose:
A possible arrangement of the straps, from the “quick-release”. (Note: this would no longer be a quick release, but may be a way to secure the shoe better, while maintaining the overall style):
“Quick release” with both straps fed under the frame:
Thanks to Mr Mooney for sharing his research with me and British Tars!