You may want to discuss your idea with the Harbormaster. He probably will let you know why he might approve it, or not. The extra connecting line between the two pennants may be there to allow for the rise and fall of the tide, or to allow for different length boats. If each
anchor has two equal-length pennants on it (which is determined by the rise & fall of the tide) they put the anchors down based on the length of the boat(s). The connecting line varies according to the length of the boat, and is
cheap and easy to adjust for different situations each season. If there was a
single line going between two anchors, they'd have to resplice new ones each time a different boat got a mooring
permit, and to keep the whole string in order, and spaced properly, when they hauled or reset the anchors. Sounds like that may be why they have the setup they've got.
To avoid snagging the line in the prop, use the
current and
rudder to angle your stern away from the line when you're casting off. For pickup, you can approach at right angles to the string. Once you've retrieved the pick up buoy line, cleat it at the bow and shut down the
engine. Then pull the boat around parallel to the string with the pick-up line. You'll have to consider the current when you do this, and try to secure the bow at the up-current end of the string. Think it through beforehand, and it should be feasible . The current in Guilford can be appreciable, (I've launched a
dinghy there, near where I think your string is) so also think about how to cut & run & try again if you have to.