Speed of HP-49G Routine for Tektronix Vector Graphics Terminal

[Werner]

You're excused, Cyrille, for not living in the hp past (42, 48/49) like me ;-)
But if you did implement the return stack update, it was probably for the 50G, not the 49G.
I remember Jean-Yves rewriting the garbage collector for the 49, making it many times faster, and - I think, it's been so long ;-) - also solving the exponential gc running time when exploding large TEMPOB lists onto the stack. But I'm pretty sure he didn't touch the ASM return stack.
Cheers, Werner