I am not looking for any info. I have tested installing from iso #4172 multiple times. I am reporting what works here and has worked for many users since I posted that article.
I know of no reason why that would be a concern. My understanding is that you are able to install from #4172 so you would have a working boot loader regardless of whether the upgrade is successful. Separate operating systems are just that separate. In any case fixing a broken boot loader is not that difficult if that should happen. There are articles regarding fixing broken boot loader in the Resources Index.