Are popes able to reform the mass on their own, or do they require the involvement of the bishops? If I am right, popes can revise or reform the mass. I am just curious why HH PB XVI hasn’t pushed for more reform of the mass other than the language revision that occured in the U.S. I know he has critiqued the way the Mass is performed today, but what ability does he have to make Mass more uniform in a way that brings life back to the liturgy? Or can he only offer his opinions and hope the priests are obedient and respectful?
The pope does have the authority to revise the rubrics of the Mass on his own. I think you are asking two different things in this question. The first part is the rubrics, and B16 has instituted a new translation for the English-speaking world. The second part, however, is how the Mass is celebrated. This is something that the pope, for logistical reasons, has less control over. The Pope and the Congregation for Divine Worship do have authority over individual priests, but the problems are so widespread, and in the majority of cases, so minor, that there is no real good solution that can come from the top.
Well he could write up another Apostolic Constitution (such as Pius V did with Quo Primum or Paul VI did with Missale Romanum) but I think he wants to make the Mass more uniform by example, such as using as much Latin as possible, Credo III, wider use of EP1, etc. He appears to be leaving the rest to the bishops.