I know that you should never use a featherboard beyond the blade when ripping a board, but what about when using a jointing sled?

I built one of these last night so I can cleanup some rough poplar. I do not have a jointer.

https://www.youtube.com/watch?v=eUubLPQozzQ

Is there any danger of using a featherboard before and after the blade just to hold the sled tight to the fence? The board being joined would pass over both featherboards. Only the sled would have pressure exerted upon it.

Thanks.