Is it OK to split infinitives?
Split infinitives should be avoided in formal writing. In formal writing, it is considered bad style to split an infinitive, but in more informal writing or in speech this has become more acceptable. ... Really is such a problematic word, it is best to avoid its use in writing and use a more specific adverb.
Why can't infinitives split?
—why it's also OK to split infinitives. ... The "rule" came about because in Latin (and many other romance languages—English is a Germanic tongue) it is impossible to split an infinitive without chopping a word into pieces; Latin infinitives are single words.