4K 25P footage in 50P timeline

Hi all,
I use a slightly older version of Final Cut pro v. 10.4.4. My question is this: if I would add 4K 25P footage to a timeline that has the setting 50P (FPS), will FCP actually try to improve the footage making it look more smooth? I always thought if the native footage is 25P then it will always be 25P. While I got that, is FCP tyring to 'create' more frames? I have run two tests and it seems that using the 50P timeline looks better or are my eyes tricked?  

Although FCP does a brilliant job at conforming footage, it won't make any difference in your case.

Usually, people shoot in 50p and edit in 50p to record fast action (having more frames/sec produces a smoother look on fast moving objects). Or they shoot 50p and edit in 25p to get very smooth slow-motion (using "Automatic Speed" in FCP). You are doing the opposite: you don't have 50p at the start but you artificially create 50p on the timeline. So you don't have the initial frames either to playback fast motion or to smooth out slow-motion. FCP will create the extra frames without an issue, but this will not improve anything.

- Ronny

This is very clear. Thank you ver much