[Nexus 6P Accessories] vido.ardes:
Sorry But I have to disagree on pretty much all of your points here.

The link I supplied is the current Battery Charging specification, and has the same information as the doc you linked. If you read the table in the picture you posted the third row clearly shows Dedicated Charging Port can have a max of 5A. This is how people can use that spec to draw more than 1.5A.

The point is that the specification are designed to artificially limit type-A ports to a lower current when used with a type-C cable. The port itself has no such limitation without deliberately downgrading what it can draw by adding an extra resistor, and the cables that flaunt the spec prove that they can handle 3A fine.

This is not true, The current USB specification (found by going to USB.org, clicking developers in the top row, then clicking documents) is the "Universal Serial Bus Revision 3.1 Specification". Amongst other things, this contains the "USB Type-C Cable and Connector Specification Revision 1.1" and the "USB Type-C Port Controller Interface Spec". The pull up resistor is designed to limit legacy cables to default USB power (see table 4-13, page 157)

Yes I did mean type-C, but your edit from charger to cable is misleading. My point there was that regardless of what cable you plug into it, a properly built charger should regulate it's own current and power draw, most transformers will limit what they can provide despite what is being asked of them, which is why a 1A charger will only provide 1A despite me plugging in a dumb cable and a device that can pull 2.4A. A crap charger however will not, and this will be a problem with ALL cables and not just Type-C 3A ones.

As with above, I'm not talking about overvoltage or overcurrent protection, the chargers that are built properly won't need to apply these mechanisms because they won't provide over-current in the first place. Think of it like when you plug your phone into a car charger, and run the GPS. A lot of the time, your battery will still drain because the charger can't provide enough power, despite the fact that if you plugged it into a higher rated charger it would. The charger itself should be smart enough to limit the current without tripping any protection mechanism, and I would expect the majority of chargers on the market to behave in this manner, otherwise we would of had reports of people burning their house down by plugging iPads into 1A chargers.

The clearest point I can make on this is from the USB Type-C spec, page 25/24 Table3-1 & Table 3-2. It states cable types and expected current ratings. There is also the below quote when talking about building a legacy cable, lifted directly from the spec:

Emphasis is mine, DFP is Downstream Facing Port (the charger), UFP is Upstream Facing port (the phone). The spec clearly states the current is to be limited to default USB power (which for the uninitiated is 5V up to 1.5A) despite being capable of 3A. It also gives you and out and says you can negotiate higher power using USB BC1.2 or a proprietary method of signalling higher currents, which is what phone and table manufactures have been doing for years.

EDIT: I just want to clarify my point. There seems to be this idea that Type-A connectors are somehow incapable of supplying 3A/5V, and that is what I am trying to correct. I have seen it here, Reddit, Android Central, and it is simply false. At the end of the day the plug, socket and wire are all able to carry 3A of current. I believe the issue the Google engineer has described, whilst real, has been blown out of all proportion, and in the real world the vast majority of these Type-A to Type-C cables are fine, and will provide fast charging when someone comes out with a compatible charger. The thing a lot of people are forgetting or not realising is that pretty much every phone made in the last 3 years isn't "in spec" either. The manufacturers have all come up with proprietary standards for drawing more current, and these latest cables are just a continuation of that process.

I think this is a perfect example where a little bit of knowledge is dangerous.