What is the advantage of an upper 2nd molar extraction with regards to further root canal? i was told i have a hot tooth.

Pain: If you have the tooth extracted, the source of the pain will be gone, but once the tooth is gone, it is much more difficult and costly to replace it. If possible i recommend saving the tooth with a root canal and crown. With a hot tooth, you are likely be sore for a while regardless. Tissues are inflammed and it takes time to control them before they fell better. Good luck.

Unsaveable: It would only be advantageous if the tooth was beyond repair and unsaveable.

Your call: Save the tooth, and you will have that much more biting surface to chew with. You will also be putting less wear and tear on the other posterior teeth. Extract the tooth, and your bite can shift, your other teeth will absorb more force and can break down sooner, and if you decide to replace it with an implant, it will cost more than to have fixed it in the first place. Save it if you can.