Yes I have. Its a deformity caused by constant poor body posture over months and years.
The point of using the 2 x 4 is mainly for the winter. The idea is that with traditional round roosting poles, their toes and feet are completely exposed when the temperatures drop to freezing. The wide flat roosts allow them to keep their toes flat so they can hunker down and use their body feathers to completely cover their feet. In my runs, all year round I have several roosting areas. Some are 2X2, others are 2X3.
In my coop I have changeable roosts. I use 2X2 in the summer, and change them out for 2X4 in the cold months.
Birds in the wild roost on all sorts of surfaces, All thicknesses of branches. You only start having body defects when you remove variation and stick the birds in one size fits all environments. Think; "Everything in moderation." and you should be OK.
Riki