My only problem is that index investing on here is often the answer to all questions and seemingly anything that isn't index-based is market timing.
So for example, reacting to a rotation in the market when you're over weighted in a sector because of gains is market timing if it doesn't involve index investing. Seriously, I've seen something close to that on here.
If my 85 year old mom has a significant enough amount of her portfolio in index bond funds, which are typically heavily weighted in Treasuries, then it might make sense to have active management in a rising rate environment. I'm not ripping on index investing here as much as saying that there are defined circumstances where a person's situation, time line, and goals will dictate the appropriate path.
There is such a thing as a stock picker's market in which index funds tend to under perform. If I have a short term goal that's underfunded, it's my hope that I wouldn't be called a "market timer" if I try to incorporate a favorable sector that the market has rotated into for the near to intermediate term. A classic example of this would be health care stocks from 2011-2015.
I like Jack Bogle, and tend to agree with much of what he says, but his quotes aren't the answer to every question or the answer to everyone's circumstance.