Biologists are not trained to do computation, and the vacuum is being filled by researchers from various other fields - computer science, physics, maths, electrical engineering, etc. Naturally, a turf battle is developing, and in his xldb talk, C. Titus fires a shot at his ‘enemies’.
The biggest claim here is that knowledge of physics is not useful to understand biological system. At one level, the claim is valid. For example, in his ‘More is Different’ paper, P. W. Anderson explained that each higher order science is different from its immediate lower order science due to symmetry breaking. So, someone with very good understanding of atomic and nuclear physics cannot be expected to solve puzzles in chemistry simply because chemicals are made of atoms. However, most good physicists know that and biology is several orders removed from atomic physics anyway.
On another level, physicists try to explain natural phenomena from a large set of mathematical tool kits. Good physicists are supposed to study and understand a natural behavior, find out the mathematical properties of the behavior and then find an appropriate model for it. From that angle, I do not see how knowledge of physics, which essentially turns out to be expertise in a large set of mathematical tool kits, cannot help in biology. However, as it happens, the physicists trained in only one aspect of physics may have used only a small set of mathematical tool kits for his PhD or so, and may get frustrated, if those tool kits do not solve a biological problem. That is more an individual issue in my opinion than general criticism with physics-based approach.
I generally observed that many thought-provoking questions asked by physicists get completely ignored by biologists, because they do not even understand why the question is thought-provoking. Leibler’s 2002 paper titled Establishment of developmental precision and proportions in the early Drosophila embryo got generally ignored by developmental biologists, even though it raised an important question regarding their most fundamental assertion related to developmental precision. Leibler continued to do interesting work asking questions on many other simple biological models, but they rarely get discussed by biologists, because biologists already ‘accepted’ the models.
If CTB wants to continue to make his claims on physics-based model and understandinf, we request him to start with Leibler’s Drosophila paper and explain why no developmental biologist loses sleep over the kind of questions raised by his paper.