That is not good practice.
You should not change one bit in a port on the line after you have changed another line.
The reason is that each instruction reads the port, modifies one bit, and writes all 8 bits back to the port.
The voltage on the port is read only about 1 oscillator cycle after it has been set. If there is some small capacitance on the port, the voltage will not have been established, and the second instruction will read porta, 1 as low so it will be written as low just as porta, 2 goes high.