200 range is the difference between rF and r1 Windmill. It's almost a 15% drop in range.
On the contrary, it is significant because the range is already short. Another example is the width of Ice Spear is 200 at F and 300 at 1, yet that 100 distance makes a very noticeable difference in practice.
Not really. Ice Spear while short, still has 1400 range as compared to WM, which only has 300 range. rF WM vs r1 WM is 66% increase while 200 extra range for Ice Spear is only 15%. In practice, that small percentage of difference isn't enough for most people to notice. Ice Spear is still short range.