sure, a gedcom file is just a compact list of names, dates and relationships, etc.
uploading a gedcom here is done in multiple stages. Stage one is the compare stage. Your file is uploaded and compared with the existing profiles here to weed out the duplicates (a task presented for you to complete)
Second, after you've marked all the duplicates to skip, then your upload is send to the admins for final approval before actually adding to the main tree here.
You can upload as many as you like. Its usually recommended to start small anyway.
The first stage, is just a comparison stage. You can throw it away and redo it as many times as necessary