1script - 4:32 pm on Sep 21, 2012 (gmt 0)
@phranque: Thanks for your suggestion! Yes, if I do in fact trust Google on what they advise for bad links handling (and I do hear lucy24's skepticism about that), it looks like I would have to create a page on the OLD site (say, default.html), redirect old homepage to it but have default.html robot-disallowed.
This feels very much like threading on a thin ice, for sure, but, again, if Google can be trusted on what they write on their website, that should stop flow of PR and remedy the negative effect of bad links while allowing actual users follow links to the homepage and eventually land on the new homepage.
As far as the redirected homepage being a link sink, I don't see that - all OTHER pages will redirect to the new locations, so whatever internal pages were linking to the old homepage, they are now not accessible and the pages that they redirect to are now pointing to the new homepage. So the old homepage appears to be standing on its own in this kind of setup. I hope my logic is not faulty, please advise if you see holes in it.
@lucy24: I actually don't really care if there are humans coming in on bad links. There will not be many anyhow: the bad links are in the footer of WP themes I've sponsored and that's not the most clicked at location on the page. I am mostly concerned about people coming from other, good sites, on a ton of good links to the homepage. In other words, the old homepage is the destination for good links as well as bad and, while I realize that I have to forgo the positive effect of good links on the homepage, I would like to preserve the positive effect of other good links that point to deeper pages within my site.
The desire to avoid creating an intermediate page (default.html, robot-disallowed) was just to avoid an extra redirect. But is still seems like a little safer approach in this slippery situation than to mess with the homepage itself.
Thanks for your input, guys! Again, if anyone sees any holes in this logic, please chime in here, I would like to consider all angles before pulling the plug.