The problem is that it rounds to the nearest point, rather than space evenly between objects as a graphics application would.
If you use it to spread out a series objects, for example ten 10 pt high objects across a 115 pt high area, they should be spaced with .556 pt between (e.g Adobe Illust). In FileMaker, we get 1 pt, 0 pt, 1 pt etc.
(115 pt, 117 pt examples)
Workaround is doing math and positioning objects manually, or figuring out the actual height for the group that would result in the even spacing achieved in graphic design applications.
An example FileMaker use-case where this is required is when a layout form prints on to paper with pre-printed rules that are evenly spaced but not in whole points. When the fields are using 9pt type, a point off every other row or two is not acceptable, especially when pre-printed rules run through the printed text here and there.
I understand for odd sized/varied objects that whole pix/points may be more suitable in some cases, but having truly even spacing between like objects would be a great option! Myself, I would set this as the default for my needs, as well as setting the default Units to Points instead of Inches.
More Design app trivia: some allow one to type math equations into in a object's height box (47÷3 resolves to 15.67)