Oh some people spin that tale all their lives! Pretend not to know something when if they were put under pressure to do it, they would be well able. It's just much easier to keep pretending, I worked with (well probably more than) one of them.Regarding point 1, I assume they sent you a new email, rather than forwarding their original one on? If I was copied into an email where someone was chasing a reply, the first thing I'd do would be to check the time and date the original email was sent.
And yeah, point 2 is annoying. I hate it when people put in a meeting over lunch and start the meeting invite with: "Sorry I know this time isn't ideal, but it's the only time we're all free". Yeah, cause it's our lunch break, dickhead, you're not important enough for me to give that up.
My rant is lazy colleagues. I'm known as an expert in a particular area of the system, so people ask me questions about it a lot. I don't mind the odd query, but a lot of the time it slows me down. Rather than complain about it to my boss, I thought I'd turn it into a 'positive' (of sorts) by volunteering to write a detailed procedure note for it. That way I'm doing something extra and sharing my knowledge, but also it should help colleagues who are struggling.
However, so many of them still come to me. I even go back to them and say: "read page X of the procedure note I've explained it in there" (and helpfully attach another copy as they've probably lost or deleted the original) as a not-very-subtle hint, but they still ask me anyway.
If people send me useful guides or procedures, the first thing I do is save it somewhere safe and think it's great I won't have to bug someone about it next time. If only others behaved the same way!
I was away on a secondment for a while and when I got back I had to get myself back into the swing of things, learn new stuff and so on. I didn't always have an immediate answer or a reference for where to look it up, anymore for the lazy one, as it was new to me too. I realised then why they do it
It makes their lives much easier. Their colleagues - not so much.