No not at all, Bunny has it down great, but the technique for that angle is sort of a hy-brid of both. But you have to admit, that sort of angle was not the norm, but more are taking to it.
But again look at the compensations Bunny makes to get the bass in that position. His basses design was never made for that angle.....if it was then it is a bad design that nesessetates the strap to travel over the front and to have a top horn/bout that adds little to the support of playing.
But one of the fantastic things about Bunny's playing is when sitting the bass is almost perfect as is his posture...two feet flat on the floor, spine angle straight and relaxed.
When you consider the first P bass designs they were a compromise to allow guitar based ideas and techniques to be played either by pick or thumb. That design was taken on board by just about all, no one really looked at it and questioned why it could not be up-right.
Emmett Chapmans stick bass took the idea close and was inovative is concept and design ( as was the steinberger ). Today there are a range of electric up-rights that use stands to support them, are fretted, easy to transport. There are even stands you can sit or fix a standard bass to that will be self supporting allowing you to move freely around them.
From the Torzal Twist ( which I love as a concept ) to players that play basses lap style, and will use modern electric stick basses on their laps ala Jeff Healy....then we see that there is more thought going into the ergonomics and techniques of what we really need to do to play, rather than play and look cool.
But what I do see is far to much justification of techniques based on traditional or accepted ideas without any real attempt to understand the mechanics involved to the players health, the mechanics are based on music.
When I was younger and playing in orchestras if a player had or developed a physical problem, they were replaced.
So I came to understand at an early age it is up to the player to take responsibility for their own playing health, because the option is not always for others to invest in getting that player healthy to play their music, it is replace them with another that can.
But yes for me in a pit situation, or one where stage movement is not what it is all about, Bunny has it down..... But I feel Bunny would have it down regardless of any bass angle or technique he used....sort of in-spite of it, not because of it.