I don't know too much about De Bakker other than his results but he does seem to be very inconsistent with often very long gaps in his playing schedule. Does this mean he is physically fragile and needs a lot of recovery time or does it reflect the fact that he is not 100% committed to tennis (study, or different reasons)?
BTW I noticed his compatriot Igor Sijsling (same generation as Thiemo) just came back after a long break and won a futures tournament in Hawaii.
If I'm not mistaken, Igor was seriously injured. He seems very injury-prone and I can't see him having a long career because of that. Also, Thiemo is much, much more talented than Igor. Still, Igor can be a solid Top 300 player if he is somewhat fit. Thiemo has definite Top 70 potential.
Anyways, Igor just lost to Niki Moser in another Future this week.