Cowpimp
Yes pure rubbish.
Doctors? They hardly know a thing about bodybuilding or training in general.
I had a doctor who told me to stop doing weights b/c he thinks I was an unhealthy weight even though my BF% was around 15%. He told me I should only be doing cardio & that 170lbs would be a much better body weight for someone 5ft10.
So don't even start with doctors. They know family medicine, drugs, surgeries & so on, they don't know much at all about training unless of course they bodybuild or have played sports themselves that require training.
As for ppl who only do 5 sets of flat bench having no upper chest development or power, I've been to enough gyms in large cities to see how these guys train & seen their non existing shape that they try to show off in their tank tops.
Yes genetics plays an important role, but if you don't even train certain areas they won't develop.
Myself for instance my chest cleavage doesn't fill out completely near the very top, it never did & I was incline benching 265lbs for about 4-6 reps & I'm currently doing 245lbs for about 5-7 reps & using 95's for incline flies with a full upper pectoral stretch & it still doesn't fill out entirely in the cleavage area. The outer area of the upper portion of the pecs fills out & connects along with the area that connect with the front delts.
It's genetic.
But if you don't even do the movements, those areas will majorly be lacking nor will you have power for those movements.