Sincere obedience will rarely lead you wrong, as long as it’s not obedience to a directive you know to be sinful.
On the other hand, it’s not the business of each individual priest to modify the liturgy. The Missal does sometimes provide several options, but in the case of posture during the consecration, “kneel unless physically unable” is the standard.
I don’t think that even an individual bishop can change that. I know the bishops of the United States, as a whole, requested and were granted permission to extend the kneeling period – from the end of the Sanctus all the way through the Great Amen – but notice the “requested” and “granted” elements there. It’s not something even the whole group of them could just decide to implement on their own.
That said, I too come from a parish where standing is the custom. We use chairs instead of pews, and though there are attachment points for kneelers, they have never been installed because the rows would have to be too far apart to fit in the usual number of attendees at Mass. I am not going to berate my fellow parishioners for standing when that’s what they’ve been told to do for years, but the fact remains that it is a matter of public record that kneeling is the correct posture for certain parts of the Mass. It has nothing to do with opinion or being progressive. I sometimes still kneel during the appropriate period, as do a few others.
Usagi