I have not read the cases on substantive vs. procedural, but to me substantive means that a recovery you would otherwise be entitled to is denied. I can think of several scenarios under which Prop 64 will have this effect. All of them relate to wage and hour cases.

One example is the waitress in a small restaurant, say six wait staff, who is subject to an illegal policy, such as tip sharing with management. That person will now not be able to bring an action under 17200 because her class is too small. Her only option is to go to the EDD but there are at least two problems: one, three year statute of limitations so she loses a year of lost wages; two, the EDD will not pursue injunctive relief, I don't think, so the employer at most pays her off but can continue the practice.

Similarly, anyone who can not meet the class standing requirement loses a year of their recovery since the Labor Code allows only three years

Another scenario that seems problematic would be a case where an aggrieved plaintiff brings an action on behalf of herself and other employees but is only aggrieved as to certain of the unlawful conduct and not others (for example, she has not been paid overtime but has been paid vacation; another employee has been subject to use-it-or-lose-it.) To the extent some subgroups of the employees can meet the class standing rules they can proceed but others may not and that part of suit would be subject to dismissal and the statute reset as to any recovery by that subgroup. By resetting statute, effected employees lose recovery and employer makes a windfall.

I wonder if an initiative simply plainly stated that all tort laws were be amended to shorten the statute of limitations there would be any doubt about whether it had a substantive effect.