Connecitivity problems France/Spain

[coupwotcoup]

Apologies if this has been covered before, but new kid on the block here. Hi all.
I travel to North East Spain (Blanes) by train about three or four times a year. Does anyone know why there seems to be such a poor connection service between Cerbere and Portbou?
So many services stop on the French side, which makes little sense to me. It is hardly Clapham Junction, with very few local trains making the crossing. Things have improved of late which means I can (if it's on time) just make a train from Portbou, which (again, if on time) connects at Massanes/Macanet.
Years ago of course, trains used to go direct from Portbou to Barca via Mataro, but these were stopped about ten years ago...
I was hoping with St Pancras opening, I could get an earlier train from Gare de Lyon, but this would be a total waste of time if one has to hang around the border for two or three hours...

 

[velaro]

I'd imagine it's due to the brake of gauge. French track is standard gauge (1435 mm). Most Spanish track has a gauge of 1668 mm. There are special installations at the border that can adjust the axle gauge of appropriately designed rolling stock, but it's still a hassle.

 

[coupwotcoup]

Yes, I do realise that and that the Talgo and Hotel trains have their axles changed crossing the border, but with such a gap between trains crossing the border (apart from goods stock), the one standard guage track at Portbou could still take a few more a day methinks.
Yes, I know I am talking from a selfish point of view, I don't understand what difference one stop makes.
Or, on a similar tack, why do the Cercanias, when they reach Cerbere, drop their passengers then reverse back to Portbou. Surely Renfe/Sncf could come to some kind of reciprocal arrangement to start their journey to Barca from the French side of the border?
I have often seen plenty of tourists, many who just wing it around the European train system and therefore maybe not as clued up as myself on how it works, looking bemused knowing they have a two or three hour wait to cross the border.
But hey, thanks anyway.