Brasso to remove swirls :S , its sounds bit aggressive.
Ok now coming to the professionals , yes they use brasso , but with the combination of other cutting products & they know the ratio through their experience & they know how much force they are applying.
Usually the combination of brasso and other products are used for cutting on repainted rides or on a old ride which was not kept with care and you want to restore its paint by starting a cutting job on it.
As far as I am concern , for small marks & scratches which don't penetrate up to the primer, I used the combination of
Mother's scratch remover + local white compound + phathar(75) rupay wali farmula1 tube;)
now why:
1-Only mother scratch remover or other top of the line scratch removers are so mild on our khota type paint:( that they wont effect much.
2- so I mix local desi compound in it to make it little abrasive
3- Some time worst quality local polish really helps you because it has oils and some abrasive content which helps in cleaning (but piyar say) cause of some oil in it.
I know the ratio what I am mixing when I do a job on scratch and mark , I feel the paste on my finger tips to get it precisely what I need & than I start with my finger tips so I can get a exact feel.
So my friend I hope your professional team know what they are doing.
Good luck.