Ask HN: Running multiple DBA (Doing Business As) under one parent company?

I have my own company (S-Corp in the US) that I use for enterprise consulting. I have a SAAS business in mind but that is totally unrelated to my consulting stuff.

Question: if I do the SAAS business, can i use my existing company as parent company and just do "Doing Business As" (DBA) with the new company ? I just want to avoid the hassles of incorporating yet again. I have an accountant who told me it is ok in my state but wanted to hear your "opinions" on what you guys think if you are already doing something like this ?

So I know the answer is technically yes but what are pros and cons of doing this ? Anything you can share will be nice