I also think that adding an option just for this is an overkill.
It makes sense that removing that cond right now would be a big behavior change and should not be done in emacs-25.
Can you guys please review and push the last patch I sent? Below are the 2 fixes:
1. Now C-u C-s shows the Regexp description if the search-default-mode is nil.
2. If regexp search is default, C-s does not show the Regexp description.
Let's continue this discussion in emacs-dev.
Thanks.
--
Kaushal Modi