It’s an interesting debate – on finances / “budgets” there is usually more smoke than light, particularly on social media (actually Welsh rugby twitter is worse than anywhere for serious quantities of BS around budgets). More than there has to be – we know what the IRFU spends on players, because they tell us in their accounts, page 80 of the 2017/18 accounts, player & management costs €37m. Remember that the IRFU is the 4 provinces plus Ireland, so this includes all contracted players in all 4 provinces as well as central contracts. This also contains costs of 5 coaching tickets and support staff, so some guesswork is required – let’s say for the sake of argument 80% of these costs are player costs, that gives €7.4m per Irish province. GBP EUR of 1.14, that equals £6.5m – obviously there is a skew in favour of Leinster & Munster as providers of most internationals (who tend to be more expensive, but also who get direct additional payments). I could believe something like £8.5m - £7m - £6m - £4.5m split between the provinces.
We know what the salary cap in England is £7m – this excludes 2 marquee players, and there are further credits for up to £600k for player development. So my guess is the likes of Sarries and Wasps will be paying £8.5m-£9m in total.
And in France the salary cap is €11.3m – about £10m.
So I think, purely financially, it’s fair to say that the Irish sides that provide most internationals have player budgets that are comparable to the big English sides, but considerably lower than most French Top 14 sides. The biggest problem for the “budget determinists” out there is the performance of the French sides year on year - yes a French side has featured in every final back to 2012, but if budgets were all-important, the QFs would routinely feature 6 French sides and a couple of English sides, which is obviously very far from what happens in reality.
I think the bottom line is that there are a couple of ways to be very good at rugby, as a club. You can either spend a lot of money on established international players and hope they all gel, or you can focus on young player development pathways and high quality coaching - a much slower burn. In fairness there is a budgetary threshold under which level high levels of player turnover will make continuity very difficult, and in all likelihood more than offset efforts under the latter model – and it also depends on having a fairly large number of young guys playing the game to a high standard, within the catchment area of the club, as well.
But if you take the view that on the whole the IRFU have pursued the latter model (by necessity) and have done so successfully, then I think some of the arguments don’t add up. When Dai Young complains that when Leinster replace injured internationals with other internationals, implicit is the idea that Leinster have gone out and “signed” them – when in fact they have developed them! (You see this on rugby twitter as well “Leinster have the money to go out and sign world class players like Ryan and Ringrose and…”) Likewise the resting players argument – Leinster and Munster can rest players and still win in the league because the players coming in are also very good, why? Because the system on average produces better players. If Leinster were in the AP, does anyone imagine that their second string couldn’t cope with the likes of Worcester and Newcastle?
I think it’s hard for English sides to come out and say that the reason they mostly lose against Irish sides because they have basically developed better squads over time and are better-coached – it’s easier to blame funding / relegation / some other external factor..
(None of this is to say that this will remain the case for ever – things move quickly, we may look back in a few years and realise that the IRFU was in an unsustainable sweet spot, that goes on to be blown out of the water by whatever comes next..)