I have an Ahab...a Large pen.
First the nib....It is a "superflex" nib. It spreads it's tines 4-5-6X or could be even 7X a light down stroke.
It requires a lot pressure to do so. At the semi-flex level....for semi-flex vs nail, semi-nail or the old 'true' regular flex....that is less.
Nail....no tine spread even if strong.
Semi-nail...if strong, 2X tine spread vs a light line.
Old semi-vintage and Pelikan 200 nibs....'true' regular flex...with a bit of spring to it, 3 X tine spread when well Mashed.
Semi-flex requires half that pressure to get out to it's max of 3 X tine spread.
The maxi-semi-flex, half of that or 1/4th the pressure needed to mash a 'true' regular flex....once regular issue to 3 X.
Next comes superflex....pens whose nibs spread their tines 4 or 5&6X or in rare nibs 7X wider than a down stroke.
This is somewhat simplistic if one has a number of superflex pens....if not as someone with only one or two....works as a guide.
I divide superflex into three categories, in that works with my 1/2 system of tine spread and pressure. These spread their tines wider than the three X max of the regular, semi&maxi flex set.
Easy Full Flex, half the pressure needed to spread a maxi-semi-flex or 1/8th the pressure needed to mash a semi-vintage regular flex ('true') to 3X.....will be wider in tine spread.
An Ahab nib will become this, with the Ahab Mod. A fun nib. My Ahab stayed in a box, until that was done to it....and it is always out now.
Wet Noodle, can not be reached with an Ahab....but needs 1/2 the pressure of a Easy Full Flex or 1/16th of a mashed regular flex....a normal nib flex by most companies until they decided to issue semi-nail instead so they didn't have to repair so many bent nibs, bend by ball point barbarians.
Weak Kneed Wet Noodle....a term developed by John Swabota who grinds nibs under the name of Oxnard. I don't have any of these and am not chasing. But they require even less pressure than a Wet Noodle.
There are dip pen nibs that make a Wet Noodle look uncooked.
One can learn a lot about feeds in the Ahab or other Noodler pens....how to make them faster, by digging out the channel or chopping off selected combs/rills. (Often superflex nibs needs a faster feed to prevent rail roading.)
Even though mine never had a problem, I did learn a lot about feeds, just by reading how to and why.
After a few days spent learning to draw the letters have the 'Ahab Mod' done...or do it your self with a Dremil or a round swiss file. Look up 'Ahab Mod' in the search section. Easy Full Flex....is a fun nib, where the as issued semi-flex Ahab nib is not.