[checker]

Your example doesn't apply because death is the ceiling. It's impossible to kill someone twice, so ultimately it makes no difference to the criminal.

However, if the criminal gets 5 years for stealing a bike, and 10 years for beating someone up, the criminal might be swayed by 5 years vs 15 years.

I can see the situation where the criminal thinks "I'm already probably going to jail, might as well decrease my chances as much as possible" by beating someone up. I think most bike crimes occur when the owner isn't around though.

[pyoung]

You are not taking into account concurrent sentencing. So if the punishment for stealing a bike was 5, and if assault was also 5, the guy would only serve 5. Theoretically at least.