Summary: It is hard to render a positive recommendation on Canon's TS-E 24mm f/3.5L strictly based on its image resolving capabilities. Image performance of this lens is more suitable for a middle of the ground, no frills, mainstream wide angle then a so claimed 'pro-grade' lens. Of course there are other factors that need to be considered here.
Conclusion: The Canon TS-E 24mm f/3.5 L is something of a mixed bag. The lens is surely able to provide a decent performance in all important characteristics but that's without delivering anything stellar ... which is something you may expect from a lens in this price class. The most fascinating aspects are naturally the tilt-shift functions and if this is a requirement for you there're simply no alternatives in this focal length class.