All valid points, especially about the clean chain. Also, when you replace your chain, replace all your sprockets too. They have worn with the chain, and putting a new chain on old sprockets will prematurely stretch it. Now about chain tension. I used to worry about having my chain too tight. I like it snug, but not binding tight. But, after watching what happens to a chain under tension, I'm not all too sure being too tight really matters all that much...
Bill
https://www.youtube.com/watch?v=7xYv...ature=youtu.be