I think he and Shelvey are very much the same but two sides of the same coin. Both of there work rates are really good. Both like to get on the ball and push foward. The difference I see between the two are as follows:
Shelvey is the shooter type, whereas Hendo is more of the passer/distrubutor. Where Shelvey is better Hendo lacks & vice versa.
Henderson is the more versatile of the two and I think can play anyone of the 3 MF roles in BRs system... Shelvey I feel is definitely the more offensive/advanced... Hell, Hendo can even sub in at RB...
The expectations are just higher for JH since he was brought in at £16mm, where we brought Jonjo in for less than £1mm