Regarding the “Barri de platja”, the opening is marked Pesant which I translated to mean slow and ponderous.
Well, literally it just means heavy. I took it to refer more to character than tempo, but I guess the latter can make sense too, and of course they would tend to go hand in hand to some extent.
We have to keep in mind that these were Mompou’s 'experiments' and if he used bits and pieces in other pieces, he could have chosen to use different tempi for the ‘new’ pieces.
Yes, you're quite right.
Well, that’s just my two cents worth. Maybe it sounds like lame reasoning, but I think it makes sense, and it works for me!
Not lame, no, and it does make sense. It's really quite exciting having to guess
how it "should" go. I now see that wikipedia suggests that a pesante tempo should be in the range 60 to 100 (but is that a modern view or did it already prevail in 1912?), and indeed you seem to be playing this at about 60 (for quarter notes). When you can next spare a moment (which I know may not be for a while), just try it at 100. Of course, having accustomed yourself to 60, 100 will at first feel ridiculously fast, but sleep on it and don't resist any "attempts" by the tempo to convince you.
I feel somewhat vindicated in my criticism to find that apparently Jordi Masó takes it at the faster tempo too. Honest, I only just discovered this, and I feel thrilled that my intuition appears to agree with his on this occasion. I don't have his recording to listen to, but the timing in the catalogue is 55 seconds against your 90, which is almost exactly the duration ratio you would expect for a 100/60 tempo ratio.
But we have to remember that professionals have to guess too, and there isn't necessarily always a good reason to prefer their intuition to one's own. So I recommend that you not
look at his timings or get hold of his recordings until after
you've first used your own intuition for interpreting these pieces.