I completely agree. It's not very usefull.
Workaround, Create a workflow rule on incident history on create, do a field update on note with a formula that strips all before 'Subject: '
With a formula field update you can do a search and left /right function like.:
Right(BMCServiceDesk__note__c, FIND("Subject: ", BMCServiceDesk__note__c)-1)
I will give that a try later today and share the results.
You can do something similar with wordings at the end, but in general it’s the full body of your email, so also previous emails.
Not that simple as we never know the ‘end’ word in an email.