Do you have any real use case where it would make sense to use I18n.to_f(number, locale) instead of I18n.l(number, precision)?
Usually an application will be either a single-language application or an internationalized one. If it is a single-language application, I18n.default_locale would always format float numbers accordingly.
If it is a multi-language application, the locale wil probably be set by a before_filter on each request from user's preference or from a URL prefix, for instance. In this case, calling I18n.l(number) would use that locale for any conversion.
What would be a real use case for the other proposal (I18n.to_f(float, locale))?
p.s: thank you for trying to reduce my frustrations, but I really don't like to waste my time. That doesn't mean I stopped contributing at all. I'm just not contributing to Rails any time soon... I'll use my free time for contributing to other projects with lower barriers, such as Redmine, some Rails plugins and others. When I have some free time again, I'll make a second attempt of contributing to Gitorious. In the first one, I've submitted a simple merge request for correcting the Gitorious name in two places (it was Gitorius in 2 places). I've got no feedback for a long time. Some day they have corrected the name but didn't update my merge request to cancel it so that I had to close it myself.
Some months ago I've modified my local installation of Gitorious for allowing tree view of the repository source-code and it is working great at my company. But I didn't submit yet because I need to organize it a bit more before requesting a merge from Gitorious commiters. But I'm postponing this because of my previous experience with Gitorious feedback. I feel that my effort will be wasted, but I'll try it anyway when I get some free time. If I don't get any feedback I'll give up on contributing to Gitorious too.
I had a much better experience contributing to Redmine and EzGraphix plugin for Rails... So, I'll probably concentrate my efforts on these projects instead, for instance...
I appreciate your words anyway, thank you.