I do have both a P6 and a T6, but I don't have an oscilloscope. I thought the DAW I am using (Logic Pro) had one as a standard plugin but could not find it. So I, instead, did a very subjective test by ear. I created an init patch on both and then adjusted the oscillator shapes as you described (for oscillator 1 and left the others off). From a purely subjective listen, they did indeed seem to sound pretty similar in that situation (adjusting the P6 shape knob slightly to match).
So the answer "might" be yes, but I would not put much faith in my ears.