I am intermittently unable to cook grenades (i.e. hold down the throw button to have the grenade detonate sooner after landing) when using a chest piece with the Mad Bomber talent active. As soon as I press the mouse button, the grenade is thrown, even though I keep holding the button down. It works immediately after I equip the loadout that has the talent, but when I fast travel to a new location, I can't cook grenades anymore. Sometimes switching to another loadout and then switching back causes the talent to work again, but this is only temporary and is also inconsistent. It seems to be fast travel that causes it not to work. The talent was working prior to TU16.
Note: the increased grenade radius, bonus armor while aiming grenades, and refunded grenade after an enemy is killed with one continue to work. It is only the ability to cook grenades that stops working.
I don't think a video would illustrate the problem very well, since a video of the talent not working would just look like a regular grenade throw.