Will nofollow affect crawl budget or backlink tools?

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  Michael Martinez: You don`t want to mess with crawl budget because that is determined by the search engine, not you.
  
  Would it affect backlink tools? YES.
  
  It would also spew a site`s PageRank back into the index, rather than allowing it to flow into the site (or to whatever sites they link to).
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  JL Faverio: What do you mean by spewing pagerank back into the index?
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  Michael Martinez: JL Faverio Since early 2008 Google has deducted PageRank from a page for every link on the page using the "nofollow" attribute. According to then-Googler Matt Cutts at the 2009 SMX Advanced conference in Seattle, the PageRank was "evaporated" back into the index.
  
  Evaporation is older than that and goes back to the original PageRank algorithm. It`s a way to ensure that every page in Google`s index gets SOME PageRank.
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  JL Faverio: so adding the nofollow attribute to these footer links would make the linked site LOSE pagerank?
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  Michael Martinez: JL Faverio Well, technically the site loses PageRank no matter what you do (it decays a little bit through each link). But using "nofollow" anywhere on the site causes PageRank to flow out to the rest of the indexed Web rather than through your site.
  
  If you`re trying to hoard PageRank or increase the flow through your site in some magical way (like squeezing a water hose), that doesn`t work.
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  JL Faverio: I know that. would you mind if I DM`d you to clarify my question? I don`t think I`m explaining it correctly. I thought the nofollow for footer links was a good thing for web designers and marketing agencies.
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  Michael Martinez: JL Faverio " I thought the nofollow for footer links was a good thing for web designers and marketing agencies."
  
  No, it`s not. Not in that sense.
  
  Where it helps is to prevent Google from penalizing them for spam. But those penalties were only applied to sites that created tens of thousands or hundreds of thousands of footer links.
  
  And there has been speculation in recent years that it no longer matters because Penguin 4.0 just ignores (removes from the link graph) any links it deems to be spammy.
  
  So don`t worry about "nofollowing" such links. You won`t benefit from doing that.
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  JL Faverio: Michael Martinez interesting. thank you Michael!
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  Francois-Pierre Marcil: Potentially the changes to the behaviour of nofollow across sites is affecting internal linking as well (ie. they might simply ignore them - think of them as a "hint").
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  Francois-Pierre Marcil: Roger Montti why are the comments hidden?
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  Roger Montti: Not sure what you`re referring to.
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  Francois-Pierre Marcil: For some reason, Facebook was hiding the conversation between Michael and Jl to me.
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  Roger Montti: A simplified answer is that if you have ten links on a page, the PageRank calculations are made so that the outgoing PageRank is divided by 10.
  
  If you have ten links on a page and two of them are no-followed, the PageRank calculation is still made as if there were ten links.
  
  What the white hats promoting PageRank sculpting were trying to do
  was to trick Google into dividing the outgoing PageRank by 8 links instead 10.
  
  So there is no PageRank savings by using nofollow.
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  Francois-Pierre Marcil: JL Faverio your nephew is a young SEO? that`s cool
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  JL Faverio: Francois-Pierre Marcil lol no just giving an example