In some places they write in the small fonts that you keep heading after the clearance limit. In others, like HTR, that you hold. All pilots need to know is the What if?.
In london, since holding is very usual, you might expect to hold even if you haven't thoroughly read the STAR.
And of course, when approaching the clearance limit, an "aproaching Ockham" call is in order.
Regarding takeoffs, in some places they give you a "turn left on course". If you do a DIR TO or intercept an SID you are wrong. You have to intercept the airway.
Canada Kid
I agree with you. i don't understand why many can't stand a discontinuity on the FPLN. Specially when you "draw" an estimated path to the runway with PBDs and such, and then they clear the discontinuity. If you forget about it you may deviate from clearance. However if navigation reverts to heading, then you wake up. Discontinuities can be used to help you.