CDED is % of total tsl always used for data and CDEF is % of total tsl that can be dynamically allocated for data but will revert to vioce if needed. A simple example :
Total tsl avail – 10
CDED 20% = 2 tsl dedicated to data.
CDEF 40% = 4 tsl that can be used for data unless need for voice.
CMAX 100% – I think this is combo of CDED and CDEF = 60% = 6 tsl in this example.
So CDED cannot be greater then CDEF since you would not be using any tsl dynamically then and have no need for it.
This is my best understanding of these parameters. If it is wrong in any way please post a detailed explaination.