Complex sentence: It was the second portion of the tour after a large North American one and featured the final performances by David Lee Roth with the band until he rejoined in 2007 and raised tensions may explain why they left the bill before the tour's end.
Split into simpler sentences: It was the second portion of the tour after a large North American one and featured the final performances by David Lee Roth with the band until he rejoined in 2007. Raised tensions may explain why they left the bill before the tour's end.