One of my students refuses to split infinitives. His solution is to put the adverb directly before the infinitive, without fail, five times in two pages of writing. Telling him to split the infinitive will go nowhere.
Examples: I need carefully to consider. . . I need intentionally to direct . . .
Another post discussed the meaning change between "I decided to go quickly" and "I quickly decided to go." In the student's examples, it is doubtful that clarity is at stake, but the order still feels unnatural to me. I've told him before that the adverb appears roughly connected to the main verb. What else can I say? This student knows grammar well and turns in otherwise immaculate work.
Or do his sentences sound natural to you?