I just compared this with BetterTouchTool which I've discovered has something called "drawing" gestures. I tried them a long while ago and had issues but thought I'd revisit them. Unfortunately, BTT's implementation is still very hit or miss with drawing gestures — whereas with xGestures my gestures are flawlessly executed each and every time.
That said, one thing that's great with BTT is I can start a gesture without holding down a modifier key or pressing a key to begin a gesture and hitting the key again after the gesture is completed as is required by xGestures.
So I've been using the BTT trial and implemented a 4 finger tap that runs this simple applescript:
tell application "System Events"
key down {control}
delay 1
key up {control}
end tell
This allows me to 4 finger tap, then quickly perform a gesture with xGestures without physically holding down the modifier key. Works pretty good but it could be better. For example, if I don't finish a gesture in time it screws things up. I'd much rather have the modifier key only "auto-lift" after my gesture is complete, but I'm not sure how to accomplish that with AppleScript or if it's even really possible with AppleScript.
So I have only one request for the xGestures dev. Please add the option to perform the start of mouse gestures with four-finger taps, etc. — That way we can simply hit the trackpad with a four-finger tap, then use one finger to draw the gesture.
That's the way that BTT can be configured to work now but BTT's drawing gestures just aren't reliable enough. For example, I have a gesture of 'down and up' to close browser windows and 'up and down' to open new tabs. Often when I perform those gestures in BTT I end up with the application switcher gesture being triggered which is set to "up and right" or "up and left". This isn't an issues with xGestures. When I do a xGestures pattern it works every time without error, ever. With BTT it's very hit or miss every other time I gesture. I made gesture variations in your BTT app to help guard against this, but it's just not helping in this case.
xGestures is still the king of Mac gestures it just needs a small tweak to allow tap gestures to trigger it.