Re: What technique would you apply to neutralize Brazilian Jujitsu attacker
"Elbow to the chin, body to the elbow" Sounds very familiar! Also instead of turning the wrist out you roll it back into your opponent. Works very well especially if you lean your weight onto the wrist and the wrist is clenched or is holding a knife.
I reckon the best answer is if you have trained BJJ guys in your dojo, have them attack you. I don't think its that easy to take down someone who has been doing aikido for a while. Even if they do you will soon work out what they are doing. Aikidoists don't attack unlike BJJ or UFC style fighting where your forced to fight. It could be frustrating for them in sparring.
Recently one of my friends who is well trained in kickboxing and grappling sparred with my students. We do an exercise where you have to defend against a person wearing 16 ounce gloves. My guys would get in easily and do sutemi or keep their distance and get kotegaeshi, mukae doashi or dogaeshi but my friend just weathered the punches and went in for double leg take downs. My top students worked out his strategy pretty quickly so they just maintained distance resulting in him often tripping over and having to use kicks and punches to distract his attackers. He called me the next day and said that what we do is far more efficient, suitable for women, old people and for him if he was sick as it required less energy. Will he change to aikido? No. He wants to do UFC ground and pound.
Aikido is self defense not a ring sport. Some of the NHB moves aren't practical against larger/heavier opponents and could put you in dangerous positions if used on the street.