YES

Rails is going to force you to use coffeescript in an upcoming version and there's nothing you can do about it.

You have to learn coffeescript now.

It can't be removed.

You must rewrite all existing apps to use coffeescript if you want to upgrade.

This is a joke by Jason Seifer (@jseifer) of the Rails Development company, Twistedmind Inc.
Twistedmind also makes employee scheduling software.
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You actually will be able to remove it but it will require removing a whole line from your Gemfile. This is significant work but adds a lot of billable hours.

Also check out Can Rails Scale? and Rails Can't Scale.
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