Complex sentence: Bols was among the top all-rounders in the late 60s and early 70s, this period overlapped the glory days of Kees Verkerk and Ard Schenk, so that he tends to be known as the third best Dutch skater of his time.
Split into simpler sentences: Bols was among the top all-rounders in the late 60s and early 70s. Unfortunately for him, this period overlapped the glory days of Kees Verkerk and Ard Schenk, so that he tends to be known as merely the third best Dutch skater of his time.