【求助】关于INSTRUCTIONS TO AUTHORS,帮看看我的理解是否正确

我第一次投国外刊物,物理方面的,他的部分INSTRUCTIONS TO AUTHORS如下:
1.Authors can submit their articles electronically via the “Author Gateway” page of this journal ( http://authors.elsevier.com/).The system automatically converts source files to a single Adobe Acrobat PDF version of the article, which is used in the peer-
review process. Please note that even though manuscript source files are converted to PDF at submission for the review process, these source files are needed for further processing after acceptance.
2.Alternatively authors can submit by sending three hard copies of the manuscript and matching disk or e-mail directly to an editor who is an expert in the field of work being submitted.
3.The Publisher welcomes the receipt of an electronic version of your accepted manuscript (preferably encoded in LATEX). If there is not already a copy of this (on diskette) with the journal Editor at the time the manuscript is being refereed, you will be asked to send a file with the text of the accepted manuscript directly to the Publisher by e-mail or on diskette to the address given below.If the electronic file is suitable for processing by the Publisher, the article will be published without rekeying the full text. The article should be encoded in LATEX, preferably using the Elsevier document class ‘elsart’, or alternatively the standard document class ‘article’ or the document style ‘re-vtex’.

我的理解和疑问如下,希望有经验的网友指点
1.可以通过网络在线投稿,并且投稿系统能把源文档自动转成PDF.我不知道这个投稿系统能否把所有类型的文档都转成PDF?
2.作者可以直接寄稿给该领域专家的编辑.如果通过Email投给专家编辑,有没有必要同时发 3 copies,编辑应该会自己 copy吧?
3.关于这一点,我是这样理解的,评审阶段的稿件不一定用LATEX生成,但是录用后稿件一定用 LATEX生成,我从没用过LATEX,需要花一段时间来学习,所以我打算先把word写的稿件投过去,等通过初审后在改成LATEX,不知这样做行不行?