Hmm...I've quit boosting my Apfelwein with sugar, it tastes much better to me this way...and I'm intending to minimize boosting SG's in the future.
I've come to view any recipe, even Jack Keller's, that call for adding water and sugar, as merely glorified 'hooch'.
I intend to become a slave to my hydrometer. Only when a full primary of pure, fresh squeezed fruit juice, fails to measure at least 1.050, will I consider boosting with a sweetener. And then, use only frozen white grape concentrate.
At least that's my "A" Plan. If this disappoints me then I'll cross the bridge to a "B" Plan later.