I think we had such a discussion before, see https://groups.google.com/d/topic/metamath/F7OY1YoGwFM/discussion
I was in need of additional variables (which could have been also primed ones), but Mario and Norm convinced me that there may be risks. Please have a look at their arguments in the referenced discussion. Alexander -- You received this message because you are subscribed to the Google Groups "Metamath" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/metamath/216b83cf-0388-44fb-ae0d-ea47f883b8a0o%40googlegroups.com.
