MSP430FR2355: BSL , signature and mass erase

Part Number:MSP430FR2355

HI everybody , 

my goal is to use  BSL  and  avoid somebody to  erase  the device and put their code on my  board ( using my logo etc ) .

If I well understood  when using BSL   with a password  ,   a bad password  force  a mass-erase  , am I right  ?     

using Signature  I can avoid this  since only a proper signature  allow me to enter BSL  : am I right ?

thank you 

regards

Carlo

PS  Jtag is disbaled by me to avoid attack from there .