Hey Jimmy...fair questions! I don't use protein powders to cover a diet deficiency, it's a supplement to my balanced diet, not a replacement for one. Expense is relative and though I can ill afford to splash the cash on anything, fitness is one thing I do like to spend money on.
But what is the purpose of this supplement? If your diet is balanced, why does it need supplementing? As far as the cost goes, I quite agree: it's your money and you can spend it on what you want; my point, was that if it was to make up for a deficiency (which you have explained it isn't), then protein powder is more expensive than protein which can be obtained through a good diet.
I can't argue a case for whether having muscle is counter-intuitive for a cyclist because I've only just got back in the saddle. However, I'm sure that having a fair amount of lean muscle can't be too harmful, and of course, it depends what level we're talking. As a general rule of thumb I'm a 'cyclist' because I cycle, but I'm no pro and never will be. Having lean muscle won't get in the way of my enjoyment for cycling!
Obviously "having muscle" is not counter-intuitive, but hypertrophy is; and hypertrophy (ie body building) is the usual objective of anyone using protein powder in the way you describe. Big muscles are more weight for the cyclist to shift (have a look at Bradley Wiggins and compare his competition and off-season weights), which is why weight training remains such a controversial subject. If a cyclist does want to include weight training in their programme (and maintaining bone density is one very compelling reason why they should) then their objective would be strength and not size: I can recommend this book.
Protein is for rebuilding broken down muscle remember - not necessarily for bulking at all. Most protein powders contain essential amino acids that aid the protein to help repair muscle that's been broken down during exercise.
As does the protein in your balanced diet. Incidentally, protein powder which doesn't contain amino acids is just er... powder.
As for the choc milkshake debate - I just don't see why you'd choose to have a chocolate milkshake as a supplement or recovery drink after cycling or any workout. I already agree that milk has its benefits, and in small quantities chocolate with high-cocoa content has its health benefits. But I just can't imagine that standard chocolate milkshakes (unless we're talking specialist stuff here?) can be a recommended drink.
Also to quote your post in the thread you started, you mention there's no difference between a choc milkshake and other recovery drinks -
I can't seem to view the studies on my phone but what are the 'other recovery drinks'?
You don't think that it might be a good idea (not to mention courteous) to read the evidence I have supplied, before arguing that I'm wrong?