I can do better than 1/FL in some cameras. TLR for instance. I am likely to enlarge the 120 negative a good deal less than 35mm, minimizing any blur from camera shake, there's no mirror slap, and I can steady it against my chest, tension the strap, take a deep breath, half exhale and hold.. I've gotten some acceptable shots at quite slow (less than 1/25) speeds that way. Not every one, but enough to make it worth a try. Usually if you pay attention you can feel your heartbeat and it you have a reasonably slow pulse (mine at rest is usually in the 60s, 60 of course would be one second intervals) you can even try to release the shutter just at the end of a beat, which means trying to do it ON the beat - the tiny delay will mean the exposure is made and ended before another heart beat causes a minor twitch.
It helps to have done some target shooting back in the day.