I believe that your approach to the issue of links that contain ?do=find is not a good SEO solution. Providing a way to add entries to your robots.txt files is not a bad idea, but in reality just blocking Google from crawling these links, won't get rid of the biggest SEO problem that they create, and I don't believe that it's crawl budget...it's all of the 301 redirects that happen due to the fact that you use such links throughout IPS software.
I believe that the best solution is simply to rewrite your code (I had a custom plugin made to do this) so that the proper, final link is used, rather than a link containing something like ?do=findComment. If you write code that doesn't use a 301 redirect it will eliminate both issues. I also have a robot.txt entry for these as well, but that alone did not help the 301 redirect issue, which my SEM Rush account had already flagged as a critical fix for my site's SEO.
