Other than that, some "single choice" prompts are there to make a narrative point... The character could be stuck and only have a real choice or maybe he is under control by somebody and the single choice is there to show that you cannot move the way you want.
Didn't single choice have the opposite effect ?
They force a pause in the action... Everything was going smoothly, one dialog line after the other, and then boom, "excuse-me an instant, can you please, mister/miss player, move your mouse and press the only button that appeared in your screen ?"
And when the action come to a pause, what it produce is the feeling that everything is under control ; the MC can take his time to act, the game can take the time to ask for your input. A lack of control is shown through an acceleration of the action ; the MC do not think about what he do, he just do it. This while a lack of choice should be shown through the reluctance of the MC ; while doing it the MC still weight his options, with the hope that he'll found something that he missed so far.
But single choice are generally used to compensate a lack of imagination, or a lack of CG.
How do I show that someone is knocking to the door ? Oh, I know, I'll put a "open the door" one choice menu. How the hell can I represent the MC undressing ? Oh, I know, I'll put an "undress" one choice menu.
By itself it's not necessarily a bad approach. There's things that are effectively difficult to represent on screen. Showing the MC undressing when everything is in a first person point of view... well... yeah, better pass. But you can easily replace those one choice menu by a timed text:
Code:
screen timedText( txt, delay=1.0 ):
text "[txt]" xalign 0.5 yalign 0.5
timer delay action Return()
label whatever:
call screen timedText( "Hearing someone knock, you opened the door." )
MC "Oh, it's you my fuck meat. Just in time"
show girlStripingAnimation
girl "Oh MC, I so want you, come fuck me !"
call screen timedText( "You quickly undress." )
girl "Oh, I see you're already hard as rock, I can't wait to be used like the cum dump I am."
And it's done. Same lack of imagination and CG, but without the annoyance that a one choice menu can add.