Hi. I have been lurking a while and hope someone may have an answer for this question. I have a Saeco Magic Cappuccino with the pressurized filter. It has been working great since Xmas but it now seems to "explode" whenever I take the filter off after making a shot. Previously, it used to release the pressure more gradually. Now, I am constantly wondering if I will be wearing grounds.
You've gotten your routine down and you get it all done more quickly? Could be affected by changes in your coffee grind, except that you are already using a pressurized portafilter which on its own could exacerbate the problem. Maybe your steaming procedure has changed?
Are you leaving the portafilter in the 'open' position after your shot?
Regardless, on any machine without a solenoid a.k.a. "3-way" valve to release the water and pressure from the group, you will have to wait a short time before removing the portafilter. 5 to 10 seconds is not enough. I would be cleaning up grounds with my Gaggia if I removed it that soon after brewing.
Don't worry so much. The only time that I've ever had "the sneeze," as I recall, is when I've accidentally thwacked the handle. It happens to people, often once -- at which point they learn to wait longer. You'll be fine!
I hadn't gone back to familiarize myself with your Saeco Magic Cappuccino to know specifically what type of pressurized PF it has.
At least some of the Saeco pump machines (like the Aroma, I believe) have a manual-release system where a valve in the portafilter remains closed until you twist/turn the portafilter to open it, releasing the espresso. This is what I was referring to by the 'open' position, should you have this kind.
Others use a stationary pinhole, or similar reduced aperture on the underside of the portafilter to allow the pressure to build up until it hits a certain threshhold and starts spitting out of the pinhole. Sorry for the imagery, but that's really what they do (and often ruin your coffee doing so ).
Be patient with your portafilter and remember to just "crack it open" a slight bit before committing to removing it entirely. This will warn you if it is safe to do so.