THAT is what I want from an OGL D&D pdf. Total effin' customizability. Give me a bigass checklist in the front of the file, like the ones that you can find in the back of old RoleMaster Companions. Allow me, through judicious checking and unchecking of little option boxes, to drill down to the exact version of D&D that suits my tastes. Give me the option of typing in additional text, or have the output of the program be in a form that I can easily edit. Then I can print out a copy for each player in a campaign and I will know that we're all on the exact same page.
How cool would that be? Frankly, it's exactly what I'm doing with my Moldvay/Cook/LL hack. When I'm done, I'll have a PDF that I can give to my players, based on the LL PDF but with my houserules in it. In essence, I'm going to be doing what Jeff wants to be able to do, but only because I have access to the Acrobat software necessary to make it happen. You could do a bunch of copy-and-paste into the word processor of your choice and do the same thing, but again, that's an ugly, time-intensive cludge.
How much cooler would it be to have a giant database of rules and systems that you could pick and choose from? Want combat to be light and simple? Pick the minimal options. Want more detailed combat, with individual weapon-vs.-armour aspects? Just check the options and activate them in your personal rules set. Brutal and bloody? Abstract and quick? Complex and tactical? Just choose the rules modules you want to use, and the rest will remain in the toolbox, ready if you ever want them. Then seed with appropriate clip-art, hit
Thing is, haven't we heard something like this before?