Unfortunately I can not answer your question as there may be a slight but important difference wiring the 2nd Generation Doorbell to a doorbell transformer.
However I can confirm that my 2nd Generation Doorbell is wired directly to the Ring plug in adapter, i.e. without the resistor and it maintains a charge in a relatively busy doorway.
One thing I will say is be careful when wiring the 2nd Generation Doorbell to leave enough wire loose so that removing the doorbell is easy as an issue I have had from day one (long before wiring the doorbell) is the Ring Doorbell disconnecting from the WiFi router which always results in having to disconnect the Ring Doorbell in order to press the orange button on the back of the doorbell to reconnect to the router. There is no issue with my router or where the doorbell is, this is simply a flaw with the Ring Doorbell. Hearing their Ring Doorbell say “Rome wasn’t built in a day” must make all the Ring customers want to throw their doorbell in the bin.
If you are reading this ‘Ring’, when the Ring Doorbell works it is great and the people I dealt with on your support are very nice and try to be helpful, but the lack of ability for the doorbell to automatically reconnect to the router is a very serious product flaw, so much so that I refuse to take the risk buying the Ring cameras which I would love to do.
Just to note that I am very familiar with large distributed software systems and networking, please Ring, provide an update to automatically reconnect.