FoPP 015 1.II.7 Hands Separate Practice: Acquiring Technique
Fundamentals of Piano Practice - A podcast by Chuang C. Chang / Henrik Pantle

Essentially 100% of technique development is accomplished by practicing hands separately (HS). Do not try to develop finger/hand technique hands together (HT) ... http://www.pianofundamentals.com/book/en/1.II.7