there is no problem with IMCS, there is a problem with bullshit marketing which prints numbers that are not real.
Most RDM masts are softer in the base/boom area than most SDM masts.
If you then use a soft based RDM in place of a stiff based SDM it will flatten the sail in a way as described by Floyd and others.
Some SDM masts are flexy in the bottom and stiff in the top and bend much like most RDM masts.
Some RDM masts are stiff in the base and flexy in the top and bend much like most SDM masts.