The shifter does not control the shifting characteristics of the transmission. The benefit of the Hammer shifter is that it looks better, It prevents you from overshifting (intending to shift from 1 to d and going all the way up to OD) and maybe quality.
In order to avoid having to do the 1-d-1 shuffle, and hold 2nd gear, you will need either a new valvebody or a shift kit.
The Lentech street terminator is a good one that allows you to hold 1, hold 2, and hold 3rd and then turn OD on an off as you wish.
Performance Automatic has a valvebody PA53301H that allows you to hold 2nd.
The Baumann engineering shift kit will raise shift points and firm up shifts, but it will still automatically shift you from 2-3 on its on, just at a higher RPM.