I think the 'French clubs don't train as hard as clubs from other countries' thing can comfortably put to sleep now. I know for a fact all the way til about the mid-2000's, the French national team was quite behind the English one for instance. But pulling that argument out now, about the Top 14 is a bit far-fetched...the Top 14 is the most intense league in the world atm:
teams and players play more games than anywhere else, certainly more than Rabo, and there aren't easy-as-shhit games in the Top 14. Besides facing Biarritz this year, even Perpignan was strong until the injuries and Oyonnax (third worse) is one HECK of a team esp. at home. We don't have Italian teams or utterly uncompetitive Welsh teams in our league. In stead of those, we have Grenoble, Bordeaux-Begles, Brive and Paris.
Teams are in constant peril of either not making the playoffs finishing a top 6 seed (like Paris right now although they're one heck of a side) - or actually being relegated and losing their capital in the salary cap and having to give away their stars and regressing back into another wild league with big teams and a rough season to prepare and live through.
I don't think with those elements, it's possible to pull out that old card, that the Top14 is behind in their fitness. It wasn't fitness that saw Toulouse get crushed in Munster, or Clermont in London. And when you see how certain sides consider Amlin as an utter joke (like Paris) or even the H Cup completely secondary, you understand the priority is largely on the Top 14 season. Teams can't play on both sides, even a strong, deep Castres or Montpellier side can't do it. The Top 14 has really become too big for its actors to think of anything else but itself.
In fact, it's become so big it's not just more important than the H Cup, it's more important than national duty !
but that's something else...
So yes, even without being on-the-spot or having talked to that many 'inside' individuals, I do think the Bouclier de Brennus is the priority over those European competitions as a whole, yes. Only the Top 2 or Top 3 teams in our league can claim or have the grandeur to actually contest hard on both sides of the season. Toulon won it last year, and they want to make history and get both the H Cup and the Bouclier. Which would be a ridiculous feat, even for the "army of mercenaries" yadi yada that they are
Now, is the Top 14 HARDER than the H Cup ? Many things can be said, and it'll vex the Irish folks because it demeans their presence in the H Cup and all...but objectively the conversation can be posed. The fact that it's just pools and then the playoffs immediately...but I think there's one big difficulty in the H Cup, it's the fact that teams don't know each other that well and the element of surprise that brings. Top 14 sides know each other well, it's a closed circuit. But here for e.g., Clermont go to London and face the Saracens. That adds a challenge for sure.