hokie66 you have a point... and going from that perspective, i was thinking of applying the "effective span" theory, (kind of like the effective length of a column), and the treating it as a slab supported on all 4 edges; e.g. a slab 2x4m supported on 3 edges free on 1 (2m span is the continuous-free), is similar in behavior to a slab 4x4m supported on all edges. but it can get tough applying it to slabs with different span ratios...
msquared48, i'm not really familiar with how to apply roark's formulas to this particular case...