The Starr protocol is for muscle belly tears, not disc injuries. I don't know which you have, but it sounds more like a disc injury. I found stretching to be one of the worst things you can do when you have an active disc injury. Generally it is better to continue training, at loads that don't make it worse. Sometimes that isn't possible right away. There is no simple formula to follow for rehabbing this stuff. I'd try doing your DLs off pins for now where you can do your setup without aggravating the injury. Don't be in a big rush to increase the weights quickly and re-injure it, but also, don't do the opposite and think the best thing you can do is absolutely nothing. You have to walk the tightrope between staying active to facilitate it healing quickly and correctly, without going too far and re-injuring it. Basically, if doing X is uncomfortable, but doesn't make it any worse afterwards, then it is good. If it results in your back locking up or being in pain the next few hours then you need to find some alternative. I wouldn't do any of your 3 options. I would just go in, try to find load and ROM I can do without making it worse and train with that. If that training didn't make it any worse, then *slowly* increase the loads and ROM over time. Most people rush that part and end up re-injuring it.