Elastic Thread Smocking

I love the clothing made with elastic thread in the bobbin but had never tried it until a few weeks ago.  I was in a fabric store and heard a lady say it could not be done on a "drop-in" bobbin machine.  I didn't say anything because I was overhearing this being said to someone else but I am thinking, I paid good money for my Brother machines (both drop-in bobbins) and surely this can be done.  Finally found a post on the internet showing the trick.  I will have to look up the site again, but the trick is to get the bobbin thread to hook into the tension and then bring the tail out and lay on the machine.  Use your needle thread to bring the bobbin thread up like you do in regular sewing machines.  Then you use regular sewing thread on top, the elastic thread in the bobbin (hand wind the elastic onto the bobbin) and just start making your rolls of stitching.  I put mine approx. 1/2 inch or less apart.  When you hit it with the seam from the iron it instantly pulls the thread together to make it look like the "smocked" clothing in stores.  Makes for a really easily made top for my 2 year old Ava.  Hopefully I will have the outfit finished before long and be ready to show you and I will look up that site so you will see the pictures of what I am trying to explain!  Blessings to all!