For me, the answer is "it depends". If I'm doing an all over FMQing design like meandering, stippling, or circles, pantos etc. I don't SITD first. But, if I'm doing different designs in different areas of blocks or more intricate, smaller FMQing I do SITD first to anchor the blocks. This is for sure more custom, labor intensive work. But, if I'm putting more quilting on it, in a smaller area I want to be sure there aren't any puckers or shifting.