OK kurtka is not allowed BJJ competition in Brazil. You must understand rules…I provide document: http://www.cbjj.com.br/english/rules.htm I put on Mizuno judo uniform or else BJJ “gi”
Your ju-jitsu tournament example not use official rules so kurtka is possibility.
I wear kurtka to ju-jitsu practice before and students make fun start jokes. Now I put on official uniform.
/ex anthropology student