Wrong, it DOES charge fine when on 100% brightness and in use. I was using it like this last night, maybe you should go buy one and see for yourself rather than spread internet gossip like an old fisherwoman.
HAHA! Thanks for the laugh. I love to hear the rantings of the senile Apple defenders as they vehemently defend falsities even when faced with facts. Here you go straight from the fisherwoman...
http://anandtech.com/show/9766/the-apple-ipad-pro-review/7
Apparently a 5 hour charge time is just fine for you and the fact that Anandtech even states "The charger also definitely isn’t enough to ensure that you’re always charging the iPad Pro while in use either if the SoC is in overdrive/turbo states as thermally constrained power draw is already around 9-10W."
I love Apple products, but I don't just buy everything they sell. I buy what I consider to be the quality products that are worth it price/value wise and a device that takes 5 hours to fully charge and won't even charge if being used on full brightness with any sort of heavy usage. They should have made the iPad Pro a usb C device. They could have had a similar 45 minute 90% charge time like on the retina macbook. Even Anandtech questions why Apple chose to limit the pro to lightning cable with 12 watt charging.