Hi Mahae, 

I know your post is over a year old but if you still view the site do let me know what they were after. I can honestly say that in 25 years of working as a BA and in project s in general, I have never ever heard of someone asking the functional requirements to be taken out of a BRD. 

Why would they want that?

I could possibly understand if they said the non-functional requirements, as once yo take them out, you give the rest (if it is SDLC) to your developers, but even then???

If it is worth anything (which is probably isn't now) I am a big fan of words and pictures when it comes to explaining requirements, so I would always say feel free to do both. If something is particularly complex or it is important that it is developed in a certain way, then a picture or mock-up as they are often called, is invaluable. 

To anyone else reading this who is new to requirements gathering a tip for you:

If you want something built by developers to a specific way - tell them. Mock it up in Excel, Paint whatever you have access to and tell your development team - that's what I want. 

If it doesn't matter too much how it ends up looking, still do a mock-up so that your developers have a good idea of what you want, it will save them asking you multiple questions. If you aren't sure how it should look, don't be afraid to ask your stakeholder or Subject Matter Expert what they think. After allm they are probably the ones who will actually use it, so they should have a good idea.