The phrase "hardly compatible" is correct and usable in written English.
You can use it when you wish to express that two things are not able to co-exist, or are not very suitable. Example: The company's outdated technology was hardly compatible with the new software.
But that, of course, is hardly compatible with the principle of the sovereignty of parliament.
They are also hardly compatible with predictions from the inner disk precession model.
Mr McCain rightly points out that the soft-money race is hardly compatible with Republican ideas of limited government.
(Italics added). This Rule is hardly compatible with a principle that a search without a warrant can be based merely upon probable cause.
Subverting the spirit of the law through such tricks is hardly compatible with the "mature debate" that Mr Hannigan claims to seek.
And Chile's foreign-trade policy, which features a flat tariff of 9% (falling to 6% by 2003), is hardly compatible with that of Mercosur.
Structural biology of membrane proteins is still in its infancy, being constrained by two hardly-compatible principles: the need of lipids for structuring the membrane domain, and the imperfect folding of proteins outside this specific environment.
Given many Israelis' objection to that outcome, to some people, the Palestinians' preference hardly seems compatible with peace.
True, the Disney demographic hardly seems compatible with his dating show, a PG-13 universe of melon-breasted bottle blondes, attempting to win his affections in dignity-free competitions like stroller derby and mud-bowl football.
He even considered settling down in New Zealand around that time (p. 153), although this hardly seems compatible with his jet-setting lifestyle.
The new songs, like the wistful, shuddering plea of Don't Let Us Get Sick, are all about the terror of ageing and hardly pop-chart compatible.
