A reading of _Mastering Regular Expressions_ leaves me with the impression that sometimes study() speeds things up but other times it just slows things down. So its actual behaviour on performance is likely dependant on your data, your regexes (which is also another sort of data) and then how often each data+regex combination is used. The way M_R_E leaves things, I'm not even sure you can arrive at any sort of truth by using benchmarks. Or... you can arrive at a local definition of truth only by testing your specific data + your specific regexes together.
The general idea is that a generalized benchmark for study() is invalid.
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