Woodsie, you are confusing royalties from sales of the music (which is administerd by MCPS and is irrelevant to this discussion) with royalties from performances of the music either live, or by having the record played on radio or TV or in a public venue for entertainment (which is administered by PRS).

Also, in the case of playing something you have just made up, the tune is clearly as yet unregistered for copyright, so none of this applies.

I agree with your conclusion, however, even if the examples were inappropriate.

Issues of mechanical and performance copyright are in fact essentially simple in their basics - it is all the extra clauses and provisos in contracts that complicate matters. The issue at the heart of the example of Steve Kowalski above is whether trying out an instrument in a music shop constitutes "entertainment". I argue that common sense dictates that it is NOT entertainment, and therefore does not require licencing by PRS or PPL.