I don't think the basal keiki is a bad thing. I used to think that a phal would only send out a basal keiki if it was near death or stressed and felt the need to find a way to reproduce or live on, but I have found out that is not so recently. One of my phals which has a very healthy root system and is growing new leaves and has bloomed twice for me, and is starting a new spike off of an old spike, has three basal keiki's growing on it currently....they aren't very big and as long as the mother plant seems happy and healthy then I will just leave it! I don't know why it has decided to grow the basal keiki's, but I think it is a fun process to watch and I'm hoping to learn something.
So what is the condition of your phal? Does it have a good root system? Is it healthy? If your phal is healthy I wouldn't see any reason to remove it, but maybe more experienced growers will have a more educated opinion then me.
Here is a link to a thread I just found that I feel has a great answer to your question:
http://www.orchidboard.com/community...t-do-i-do.html