Ok, I didn't realize that. No difficulty taken!
The aftertouch on my A50 is not as easy to engage in its default setting as I'd like, but can be adjusted by changing the sensitivity setting, so that it's easy to engage. I always figured that A80's must be the same, at least when they were new, but I guess that's not the case.
I have tried a couple of used A80's before, I was considering getting one to augment my A50. And it was truly amazing how difficult it was to engage the aftertouch - almost impossible, even after adjusting the sensitivity to the max. I always thought the ones I had tried must have been worn out.