SpaceX does suicide burns because of engine throttling issues; that's a separate issue from margin, and a separate issue from landing on a barge vs landing on l

SpaceX does suicide burns because of engine throttling issues; that's a separate issue from margin, and a separate issue from landing on a barge vs landing on land. It remains to be seen which of these are dangerous enough that you don't want to do them with a rocket you want to land many times.