Arm Bar variant

This week I started doing arm bars in a manner that I saw on a You Tube vid some time ago. I can’t locate it now unfortunatly. However, this how it goes: Begin the arm bar in the normal fashion. While on your side, with the bell vertical and shoulder packed, keep both legs straight and together. Do not move the leg out at this point but maintain a vertical arm balancing the bell. Maintain complete control and try to find the true vertical for control for 5-10 seconds. Then slowly move/push the leg out and assume the arm bar static hold with hip bone close to or touching the floor. Maintain for 10 seconds. Then slowly pull leg back until feet are together and again find true vertical and maintain control for 5-10 seconds. Is there any benifit to doing this kind balancing during the arm bar? Has it something to do with "proprioceptive mapping" ?…I am not sure what all that means, but would like to hear from those who know…Dennis