Yin offers various options for support... yes, I mean PROPS. Using props provides an array of support (whether it's simply for comfort, or to bridge a gap or space between you and the floor, or to alleviate that tension when you are 'hovering' with resistance) but ultimately to allow you to relax and then be still in the pose, despite how challenging some of those poses can be. Included in that array of items (bolsters, blocks, foam blocks, pillows, blankets, cushions, straps, etc.) one can also simply add the support of... the wall. Particularly when you don't want to do anything but collapse and be supported. So, whatever your prop of choice (wall included), if you haven't tried one or two in your yin practice - why not explore and be curious to the benefits it can offer. If only to be adventurous... you just never know.