Funny old world innit? Enough is fine until there's more. Consider the evolution of the touring trail bike:
Yamaha XT500> XT550> XT 600 > tenere> TDM etc.
the air head BM GS's > 1100,1150,1200 oil head GS's> hypothetical 120bhp 1250 GS
All that's happening is that in order to control the extra power and speed that we all are apparently so desperate to have, the brakes have become bigger, the tyres wider and softer and the suspension shorter and harder. At some point these are no longer trail bikes and are simply comfortable sports-touring bikes with tall bars. In other words a sensible everday motorbike like everyone would enjoy riding if they weren't so obsessed with image or brand or so easily swayed by what they read. With a sensible bike we would of course feel inadequate because sensible is slow, Honda, effeminate, average, grey and ordinary. Even though we could on such a sensible bike (like the GS) ride for many happy hour without getting back ache pretending to be Rossi or getting a nasty tattoo in order to ride a Harley we'd still rather not if it spoilt our image. Proof of this is the difference in sales between the GS and the 1200R, essentially the latter is a better street bike but we'd rather feel special on our GS's as it gives us a bigger grin and feel good factor as we know if we only had the bottle to give up our jobs we could all nip down to the Cape like Charlie and Ewan, one day eh? Maybe? Yeah right.
A 120bhp 3-4 cylinder GS 'evolution' would be nothing more than a dog slow Yamaha FZ1 Fazer that cost twice as much, so why bother?