Funnily enough, Ivy, JM reminds me of my late brother Fred, who once owned one of these before he bought his last car. Since the mechanism for disengaging the clutch didn't work worth a damn, Fred would "slam shift" his. The trans didn't last long under that.
You could shift them that way, if you have enough practice. The only problem would be at take-off. In that case, you'd have to use the starter at green lights