Reset and Trigger connected in 555 timer circuit
The 555 won't work 100% in the monostable mode anymore,that's for sure.In your suggested configuration,when trigger is pulled low,reset is pulled low,too.That means it sets and resets itself at the same time.

The result is rather unpredictable,as someone states in a comment.If reset turns on first,chances are the IC will work in monostable mode.If trigger switches on first,then the output won't turn on at all.It's like playing the lottery.You don't know what's going to happen.

I don't see why they would need such a setup,either.It can only lead to an erratic functioning of the IC.Setting and resetting at the same doesn't sound like a good idea.It is supposed to be in one of the states at a given time,not in both at once.

Perhaps the person you speak of thought of using the 555 in astable mode.That requires the trigger to be tied to the threshold pin,not to the reset pin.That way,after the voltage across the capacitor reaches 2/3 of \$V_{cc}\$ ,the discharge pin activates,until the voltage changes to 1/3 of \$V_{cc}\$,trigger activates,discharge is deactivated and the capacitor starts charging again.

Neither the bistable mode involves your suggested configuration.In this case,trigger and reset are pulled low independently.

To conclude,nothing useful would happen if you tie reset to trigger.The suggestion is a mistake in my opinion.