Yes it is, but it's not the last in the process so any residue should be removed in the following process.
It's actually quite good during the build as it tends to show finger prints less and resists the tarnishing marginally longer, important if you're doing photos of the build, it's a PITA having to keep going back and cleaning the last sub section to make it bright and fresh when you add the new section.
I tend to wash the whole thing in thinners at the end just before applying paint and that seems to get rid of anything that went before.
MD