Your routine is very gentle with the twins but feels a bit detrimental to your mental state. Parents also deserve to get some rest. We implemented an adjusted version of the CIO method. At least with ours it worked quite well if they were both fully fed and dry. Emphasis on fully fed, as much as they can, we give them my milk but in bottles so we could measure feedings better. Once they are fed, we put them both in their cribs, same room. Yes they used to cry for up to 10 min but we found that reasonable. They'd cry for 2 min, stop, cry for another 2, stop, cry again and finally fall asleep. It's not easy ignoring it, but it worked super well and we all got proper rest. Now they are 4 mo and sleep 11-12 hours per night, and no issues with naps or bedtime anymore. I know some ppl say not to sleep train until they are 6 mo, but you know your babies best and if their needs are taken care of, no need to rush in after a minute of crying. Ofc if the crying was different or lasted longer than 10 min, we'd go and check, was usually that they pooped themselves right after putting them in yea. Depends, just follow instincts, but yeah you also deserve a break. We found that they did not wake each other up, maybe they got used to it.