Generally, when something was too small for a hole, it just slipped right through it. It was a fitting analogy; Tony knew plenty about having a hard to fill hole in his chest.
Immediately -- maybe sooner than -- Tony was sure it had been a terrible idea to ask. Simon was probably a perfectly fine person, perfectly capable and smart. Which was why, of course, Tony disliked the very idea of him. There was no point in having a green monster of his own when he was friends with Bruce, but there it was sitting on his shoulder even when it didn't matter at all. It wasn't like Tony felt like there was any danger here -- Steve was sticking around for good. Knowing things logically never quite matched with emotionally, though.
"But he was also in the frozen dinner aisle," Tony pointed out.