Well then here is some evidence...

"Unusual Creativity

LD/ADD students are usually much more creative than their classmates. They approach problems in an exploratory manner and express themselves and their ideas in a more open-ended way. From poems to mechanical inventions to business ventures, they tend to keep tinkering with their design long after others consider the creative process complete. The products of their inventive thinking are often so simple, yet so totally original, that others gape in wonder, saying, "What an ingenious idea"."

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I expect I will be able to find more.