I've never heard of such a scenario, but assuming arguendo that your lease is really in such small print, it is possible that a court could deem it unenforceable.
Certainly, as to certain disclosures required under California law, the lease actually has to be in a certain font size. For example, regarding Megan's Law, Civil Code Section 2079.10a, the notice used must be in at least 8-point type. For condo conversions, Government Code Section 66459, this notice must be printed in at least 14-point bold type.
Frank W. Chen has been licensed to practice law in California since 1988. The information presented here is general in nature and is not intended, nor should be construed, as legal advice for a particular case. This posting does not create any attorney-client relationship with the author. For specific advice about your particular situation, please consult with your own attorney.