A free climb too hard to aid...

Random thought here. Disclaimer: I have pretty much 0 Aid experience of any kind.

Are there any climbs the have been freed that would be impossible to aid cleanly? Or is it fact that if it can be climbed free it could also necessarily be aided. In theory could the cutting edge sport routes be aided?

Obviously I am talking about aiding with hooks, clean gear, etc; no drilling or using in-situ bolts etc.

Just a (probably ignorant and misguided) thought

If it was a featureless stem or an extra large offwidth with normal gear it would be impossible to aid while it could easily be freed. Slab climbs would also be near impossible to aid as well as climbs where all the holds are smooth slopers.

some routes don't have features for natural progress from hooks, pins or clean pro. you could always make a bolt ladder to get to those features. If the route could be freed then the bolt ladder is unnecessary. you can always drill hook holes to get through truly blank sections to place a bolt where it needs to be.

the real question is goes free for who? under 5.13, 5.12, 5.10? R rated start, X rated? where is the line?

but if you drill hook holes/RB's for steep rock there is nothing you couldn't aid. On a Fa that's how i would get to the stance i wanted for my first bolt.

but if its that blank its going to be very hard anyway

your question made me think of Mean Black Dog 5.12 at the selfish wall in Indian Creek. no crack for the crux, so no aiding through, just big whips.

Clean aid maybe not, but you can always put up a bolt ladder in almost anything.

Sure, plenty of face climbs with sloping holds that a hook will not hold.

I seem to recall Ammon saying something to the sort that he climbed an A5 on El Cap that had a crux pitch which would probably go free at 5.10 (X) if someone tried to free it. No idea if it's true, but it's certainly plausible.

Snake Dike in Yosemite, while rated 5.6 R, would probably go at A5 if aided simply because it would be nothing but shitty hook moves forever with no pro and pretty much little to no options for heads.