Anyway, apart this, I disagree that M&S is the strongest shield. S&S has more damage vs hordes. A&S has more armors damage and its bash is even faster than a standard bash. Without talking about about BS&S and Elf Shield, wich clearly maintin their pros.
Anyway, if Fatshark started to think that M&S is too strong, there would be better ways to balance them… a malus on the bash, one of the fundamental shields’ features, seems to me silly.
I’m not sure I have understood what you wrote… but it should be a bug, look the link I posted above.