Not sure I agree with this. I tend to use way too many tabs, and therefore use up my memory. I was visiting my parents recently, and on their Mac they were le

Not sure I agree with this. I tend to use way too many tabs, and therefore use up my memory. I was visiting my parents recently, and on their Mac they were leaving a lot of programs running (having closed the window but not exiting the program). I think low-memory situations are the most likely explanation for slowdowns experienced by typical home or office users.