Let me put it another way. If Hitmonlee is forced to run a dangerous counter like that. Than I think Claydol has already done its job in countering Hitmonlee. It makes it even more vulnerable to priority attacks on its weak defense and prone to massive ammounts of recoil damage.But even Claydol cannot avoid a possible 2HKO if the opponent decides to be Reckless, which is legal with Double-edge as Tyrogue gets it via Emerald Tutor. Of course there are downsides to this, such as sacrificing para-immunity and the huge recoil, but if it allows Hitmonlee to 2HKO the only decent counter it has, people may well be tempted to try it.
On Gligar:
One thing actually impacts the whole OU-lite Gligar issue. That would be the stat distribution, Gligar to Gliscor gained 10 in each stat but got +20 base in defense. Now Gliscor's main use tends to be for defense but -20 defense opposed to -10 in the other stats changes Gligar's distribution significantly. In fact all the other stats Gliscor gained in only just pushed them into average or above average. Gligar remains subpar in most areas. I do think this actually changes Gligar's use abit.