Back to the question
I can't comment on UK vs US methodology, but to get back to the OP's question:
In my early training I once did around 30 hrs in 10 days. For me this was fine, I interspersed flying with theory, and I mixed up the aircraft types (at my behest), so it was never a dull moment and I never felt particularly tired.
Later on I was associated with a school; it was clear to me that people learn quite differently, and what works for some won't work for others. That said I met a number of people who learnt, whoa to go, in a very short time (one did a complete PPL in two weeks). In my view these people were 'better' than those who'd taken say two years to get to PPL, however I suspect it wasn't just the sustained training, personal attributes will have had a marked effect.
If you're a self starter, and a reasonably driven sort of person then I'd certainly try doing several lessons in a day. It's all experience and you'll soon figure out if it works for you or not.
FP.