Credibility Zanash.

Some ideas can and should be dismissed out of hand for this reason if for no other reason than to save wasting brain cells.

I'm aware of Thorsten's 'reputation' - in as much as familiarity with his hi-fi fora postings and contributions elsewhere - and clearly the man is a very knowledgeable individual. However I'd still dismiss the idea of small strategically placed dots to influence the room acoustic as lacking credibility.

With respect to both yourself and Thorsten, the man to ask for a qualified opinion would be an acoustician by the name of Eric Desart. He posts on the Sound on Sound forum.

Now I suppose I could try these dots as you suggest this is the best way to proceed. I could also try to make apples fall upwards. The issue here is not nay-saying.