So, you're a new postdoc or grad student getting ready to write your first proposal for something like a fellowship (say, for example, a K99/R00). Where do you start? Most PIs will happily share past and current proposals, and even encourage you to use them--this can be great, because it gives you a review of their spiel for the story of the lab, a ton of relevant references, covers the main background, significance and motivation points that will apply to many common projects coming out of the lab. For many funding agencies, it's not even considered plagiarism to use their text/figures word-for-word, as long as you disclose the relevant contributions by you and your PI (i.e. what portion of the proposal represents your own independent work and what came from them). There's a huge difference between using common statements and data from a given lab, with attribution where due, and going out to find other labs' stuff to put in your preliminary data, and after all, it saves time and effort and is much more efficient to just use what already exists rather than reinventing the wheel, right? But I think there are several important reasons why trainees should do their work from the ground up, starting as early in their scientific lives as possible.
You need to develop your own deep understanding of your work, and not just become a parrot that repeats what someone else has told you about it. Working from someone else's grant, it is all too easy to just reword phrases they used, use the same paragraph structure substituting different terms for things, etc. But unless you understand it at its most fundamental level you will just sound awkward doing that. My students all got a copy of my K99 when we started the lab, and for their first few written reports (which I have them structure like a grant proposal/committee report hybrid), their intros and motivational descriptions were all just strange, awkward reworkings of my grant. Sometimes the sentences didn't even make sense, sometimes paragraphs were just odd rehashing conglomerations of things I'd said. It was clear they didn't really "get" what was going on. It wasn't until their third or fourth times through writing about things (as well as their completion of a lot of grad level coursework, a grantwriting class and holding their first committee meetings) that they moved up a level. In all those pedagogical experiences, they were being taught how to think and write from the ground up, and it made a huge difference in their fundamental understanding of their work.
*by the way, they know about this blog and I have their permission to talk about them here 🙂*
Another key thing is to watch out for believing your own lab's hype. Your PI will likely have thought through the rationale she/he presents from the bottom up, reading the relevant primary references that she/he cites and making a case for the work proposed. Some of that case-making always involves setting up straw men and pushing an agenda. If you take your PI's rationale(s) too seriously without doing your own due diligence and going into the surrounding literature, you are at a major risk for believing yourselves too much. As a communicator, sure, you need to "tell a story," but as a scientist, you should NEVER blindly believe your own story. Another thing I saw in my students and postdocs at first was a face value acceptance of my "story" for our science. Heaven forbid, they *believed* me and I had to tell them not to! They were all too ready to assume that I must be right and have the right hypothesis, so for any data that didn't fit, it must be the DATA'S fault, not the hypothesis being wrong. This was both a lesson for them and for me: that I have to be careful--when recruiting people to a lab, you have to convince them your stuff is cool. But as soon as they walk in the door, you want them to start as skeptics and work to convince themselves.
You also need to learn how to write with the training wheels off. Your PI's grants might be a good baby step to help you wobble along, but unless you actually know HOW TO WRITE a grant, you will not have it easy in this business. Even if you know you'll never want to work in academia, this kind of writing is extremely common--my husband works in industry and has to convince higher-ups to approve megabucks projects all the time. He has to use the same strategies to provide rationale for this, both written and presentational. There are a lot of more open-ended training tools and guides you can use (I am a super big fan of this NIH Workbook from Russell and Morrison) that will help you use your OWN thoughts and information from the primary literature to build your case. Once you really sit down and pay attention to what you are trying to say, you will make a lot more sense. One of my students had major troubles with constructing paragraphs that followed a logical plan--he tended to just randomly pile his points in a jumbled order. Then after I returned from maternity leave, he had his first committee report due. I was worried, but when I saw his draft his writings seemed transformed: he was making a lot of sense and building a strong motivation for his project. I asked him if he'd started doing better at using his resources for editing (friends, writing lab, etc.) and he said, " Well, mostly I just started to actually READ what I was writing to make sure it made sense." Another of my students found that the workbook was incredibly helpful to order his thoughts (which, while excellent, creative and awesome tend to miss the page and end up in the aetherland when he sits down to write)--he produced a proposal that was very close to passable once he found the right tool. Voila, not-so-magical progression in both fundamental understanding and ability to communicate.
When it comes down to it, using someone else's writings in your proposals as a trainee just isn't worth what you trade for that time. It's a false economy, since it'll result in setbacks to your depth of knowledge and personal skillset, and you might as well just start early on learning how to do this stuff. You're going to suck at first, and it's always useful to have someone else's writings as an example to see roughly how to construct a document, but you really need to be preparing your own content from your own brain and ruminations in order to get to where you need to be in this business. So just bite the bullet and start reading papers--someone else's grant isn't going to give you all the answers.