LScamper,
In my studies, the issue becomes a problem when you parallel very long strings of LEDs, where the forward voltage between strings varies more than a few millivolts. Driving short parallel strings of high-power LEDs is endorsed by Diodes, Philips and most other sources I have worked with.
For long strings, such as signage lighting or LED back light, each string has at least a ballast resistor, or more likely a linear regulator in series, insuring each string receives only the design current even though forward voltages vary between strings.
