Wow, they do? When I turn up the light on mine, they just burn and the leaves brown and die. Mine are under moderately bright light, and stay about 4". I had one get to 7" across in weaker light, but the over-large leaves died off when the light was increased, and it is now a steady 4" around like my others. All maintain a nice healthy light green color, with bright red tentacles.
The pictured one is totally unlike mine, perhaps if this is a mutant, but still shows the typical D. adelae propensity for large numbers of plantlets, the plantlets will share the parent plant's mutation and we can eventually all get some mutant moving sundew action!