Mend and Minor Maker Spells

On page 216 in BWG both of these spells read like they should last beyond the susained time frame (and I ran across an old thread were that was indicated by Luke), I am wondering how these spells were put together and why these spell facets were chosen. (I would have thought Permanent rather than Sustained Duration on both and Earth rather than Heaven Element for mend, unless the Heaven facet has more to it than just light) Also, though I recognize and appreciate the nod towards Mr.Gygax in the Magic Whistle spell, what elements and impetus should be listed there?
As this spell obstacle has no exponent, the Magic Whistle gets to travel about three feet into the air before in pops and drifts sparks back down. (A Pace is about three feet isnt it?) I believe the original in A D & D (2nd.) went higher (5 - 10 paces?). If it had the exponent, the height would depend upon the casting successes greater successes equal more paces so 3 or 4 successes would mean 9 or 12 feet wouldn’t it? (or am I missing something with these assumptions?)

I think that Heaven element for Mend is errata! Quick, someone errata that!

Magic Whistle is a joke. Cast at your own risk.

Don’t dismiss Magic Whistle like that, Luke! Look at Shaun’s AP videos, and see someone use Magic Whistle to acquire not one, but 2 Persona points…