am i right that it kinda creates second 'block' only after exceeding 200mb?
Apart from the MFT-header BloodySword mentioned, the main part tries to stay in one piece until there is a file at it's end, blocking it's growth. So it has to fragment itself to grow further. Some defragmenters (including MyDefrag) can defragment the MFT since Windows XP. The problem you can run into when using an optimization script instead of the Defragmentation script is that MyDefrag can wrap the MFT around an unmovable file, hence fragmenting it.
P.S. Some software states, that the read speed from those 2 fragments is 2x the normal read speed of my HDD, so that's why I thought this issue ever worth mentioning.
Which software does that? It is likely that MFT has been cached and the software is reading it from there, bypassing the slow HDD.