'Enjoy Oneself' As Behavioural

The clause is agnate with he is enjoying [[what he is doing]].

The unmarked present tense is 'present in present', like behavioural, rather than mental clauses (cf. he likes [[what he is doing]]).

Here 'enjoy' adds an emotional feature to a behavioural Process.

'Portray' As Relational Process

In Deploying Functional Grammar (Martin, Matthiessen & Painter 2010: 124), portray is interpreted as a behavioural process, despite it occurring in effective clauses, and despite its Range not being a behaviour.

'Sneak' As Happening, Doing, Behaving And Targeted Saying

The lexical choice of 'sneak' adds a Quality feature to the Process.