I somehow agree and disagree. Aikidoka are not only not psychologically prepared, but also from technical point of view they often don't any idea what happens AFTER they enter\irimi into attack. Such scenario with uke alive (means i.e. bouncing and disengaging only to re-attack) is never done.
On the other hand, a simple irimi is often not sophisticated enough as a solution. Advanced attacker will early see the intent of entry and will modify his behavior. Here I agree with Dazzler that we have to carefully study peoples behavior in different situations do develop our eyes. I strongly believe that aikidoka must become a master of reading body language as a first step to his mind training.
There shouldn't really be much of an after the irimi. The entire point of Aikido, as I see it, is to break balance on contact. That's the foundation, if that's not being consistently achieved then the Aikidoka really needs to make an exhaustive study of it. The most sophisticated part of Aikido is the irimi movement because that's where, pace the ISers, that's where the Aiki is.
The worst case senario is that you mistime your irimi or get caught out by a feint and they back off, in which case you chase after them. If they're going back I don't let them pause to get a base to strike me from. I can do Aikido on the run, few people can effectively strike on the run.
As it is I don't find that even quite skilled martial artists read what's going on. Aikido's approach is just too unique. I can't think of another art where people respond to a strike by moving forward, except maybe BJJ and their method of entry is different although the principle of kuzushi on contact is still there.