1. Enormeous port currents will flow, when emitting low level. Especially, if not only one such driver is used.
by my calculations 4-5mA, is that 'enormous' in your neck of the woods?

2. Due to the fact that still a pn-junction tears down the potential at port pin to about 0.7V, a read instruction of port pin will result in an eroneous logic low level state, although 1s was formerly written into the SFR, means although the correct logic level of output is "high state".
who cares about reading a pin used as output. If you need to, your code is not particularily smart.

Erik