On the rare occasions mom used a Fleet type enema for me she sometimes would take her time in squeezing the bottle so it entered slowly but sometimes she'd give the bottle a hard squeeze and the cold enema would squirt up inside of me invariably making me gasp. This quick squirt approach often happened when she'd opened a two pack and if I was OTK. She'd open the box, take out the first, inject and often say, "I'll give you this other one too. That will be sure to get results." The second one I'd get firmly, but not so aggressively. Mostly though I'd get a single shot, not too aggressively.
She always had several two packs as well as singles under the sink. When she'd see on sale, she'd buy several be it singles, two packs and even I think it was four packs.
My wife also has always kept squeeze bottle enemas on hand and, like mom, what's on sale. She often uses these herself not for constipation but when for some reason she wants to go out with an empty bowel. Before a long car trip, a flight, or even an afternoon golfing. When she uses on me if I'm OTK it will be a firm but not rushed injection. On the other hand if she has me in the diaper position I can be fairly sure she will squeeze the bottle as hard as she can and send my eyes a popping.
I got to thinking about this as I was putting away shopping a few minutes ago which included a couple of twin packs she'd noticed on sale and I wondered how others have had, or give, bottled enemas .... fast, probably average, or maybe really slow?