SO, which is it to be this Sunday - Jason's day or Ryan's slaughter? That is the question consuming Kildare fans, caught in that no-man's-land between hope and terror, as they look forward to their Leinster SFC semi-final against the supposedly invincible Dubs.
Even during this unparalleled era of provincial dominance, Ryan can boast a track record of pushing Dublin to the brink and almost beyond. Three years running his team could, and probably should, have ambushed scorching-hot favourites in sky blue.
Only one problem for all you Lilywhite dreamers: Ryan was then managing Wexford.
Here's another problem: all this happened in the Pat Gilroy era when Dublin had a tendency to splutter through Leinster before (usually) raising their game to a higher pitch. They have been a different and more ruthless provincial beast under Jim Gavin, with the result that only Meath (in 2013) have managed to avoid a double-digit defeat.
Nowadays, Ryan is in charge of Kildare and - up until that very recent replay triumph over Laois - he was a manager under pressure. He had overseen back-to-back relegations, with the result that this putative top-eight county will be playing in Division Three next spring.
That niggling reality won't change, come what may over the coming weeks ... but Kildare supporters are such incurable summer romantics that league status won't matter if their team can start to challenge for championship honours in the meantime.
It remains a huge ask, for myriad reasons, starting with the obvious fact that one victory over a county with collapsing tendencies doesn't suddenly make you ready for Dublin.
Yes, Kildare's early second- half blitzkrieg of Laois bordered on remarkable. But it must be taken in context, and lowly Antrim provided plenty of that only last Saturday, coming from nine points down to banish the meandering O'Moores to an early back door grave.
The hope here - for the health and future well-being of our ailing Leinster patient - is that Kildare will deliver a performance of substance next Sunday. That they won't fall away tamely as they did when losing to Gavin's Dublin by 13 points in the 2013 league, or by 16 points in that year's championship, or by ten points in last year's league.
Ryan was a Kildare selector under Kieran McGeeney for the first two of those defeats, and main man for the third. His time in charge of the Lilies has been blighted by countless injuries, player retirements and defections overseas, with the result that only a handful of McGeeney's team (from their 2009-11 pomp) remain central to the current project.
They are a work in progress, still capable of sky- high wide counts (16 the last day) although in fairness, over the course of 140 minutes, they had a definite edge on Laois in terms of fitness, pace and athleticism.
But that was Laois: this is Dublin. Nothing Kildare have faced this year will have prepared them for the rapier pace of Gavin's team. Or the sometimes overlooked prowess of their tackling. Or the speed and clinical efficiency with which they punish turnovers.
For Kildare to make a mockery of their 12/1 odds, they must hope for a rare Leinster off-day from the 1/25 favourites - for the rot of complacency, perhaps, to set in.
Even in that scenario, the job won't be half-done unless they are set up with the right balance of pragmatism and ambition. Parking the bus alone won't suffice, but going man-for-man could constitute suicide. They must soak up the onslaught, force mistakes and then punish every one of them.
If all this sounds like a ticket-selling fairytale (copyright Leinster Council), don't forget Ryan's track record against Dublin.
In 2010, Wexford led by seven points deep into the third quarter, but were eventually forced to extra-time where they fell away to lose by seven. In 2011, Leinster final history beckoned until a bizarre own goal turned the game on its head and Dublin won by a goal. A year later, they led their Leinster semi-final by three at half-time only to lose by four.
Woulda, coulda, shoulda? Perhaps. But, each time, Dublin were blessed to escape.
Jason Day, all you golf nerds know, is the Australian who bravely battled vertigo to challenge for US Open glory last weekend. He collapsed, literally, but refused to stay down.
Ryan's Wexford faced their own vertiginous challenge, in those above three matches, and went down fighting ... now Ryan's Kildare must deliver something equally courageous.
For Leinster's sake, as well as their own.