1. In my experience, you don't need to provide any documentation unless the merchant disputes your chargeback. So you should keep documentation, receipts, screen shots, notes, but not worry about filling out a detailed initial incident report.
2. Some people have claimed that you risk running afoul of your credit card if you use this feature too often. I'd say I use it twice per year and I've never been hassled.
3. Morally, I think you're just obligated to make a single attempt to rectify a misunderstanding with a merchant.
4. My credit cards let me fill out a report online, which makes this extremely convenient.
they're also excellent about managing chargebacks, like when a chargeback comes through and you've already given a refund. this is so frustrating with Visa -- they'll actually still process the chargeback and ding you $20, even though you've already given the money back.
AMEX not only provides the best interface to manage chargebacks, but they also don't charge a chargeback fee at all.
I cancelled a subscription to XM and they kept billing me. I called to recancel and get a refund, but neither happened. So I did a chargeback.
That's typical of the experience that would lead me to file a chargeback. If I was billed for a service that I didn't receive and my first attempt to go through customer service fails then I immediately ask my credit card for a chargeback.
That seems fair to me.
Also it's a huge pain in the ass to dispute, even when the merchant is obviously right. Most small merchants fear chargebacks, not so sure about big companies though.