Looking for XY Poke Radar advice/guidance

[RedPotato]

I'm brand new to these forums, but I've been catching shinies for a long time now. I've read a lot of guides and watched tons of videos on the various methods, succeeding repeatedly with every method I've tried except for Poke Radar in X and Y. So far the only shiny I've managed to get through that method was a Croagunk that appeared after a whopping 1 encounter. The only time I chained past twenty was with Weedle in Santalune Forest (got it to 40, then accidentally stepped into a shaking grass spot I hadn't seen that broke the chain). The rules I've been following are below:

• Only go for a patch of grass at least 4 spaces away in one direction.
  
• Never go for an edge space.
  
• Only go for the most violently shaking patches.
  
• Never go for a patch when an adjacent patch is shaking (I've heard conflicting information about this but have been playing it safe).
  
• Never move away to the point where you can't see any of the shaking patches when resetting the radar.
  
• Only go for a patch when you can see all 5 shaking patches (I sometimes ignore this rule when my chain is below 5).
  
• Catch the pokemon instead of knocking them out (this rule made a huge difference for me in Diamond and Platinum, but I don't know if it still helps in Gen 6).
  
• Upon hitting 40, only look for a shiny patch.
  
• When in doubt, reset the radar.
  

Are there any glaring issues that any of you can see with my methods? Anything that conflicts with the rules you've used/succeeded with? Or am I finally just unlucky?

[RedPotato]

Update: Since posting, I got to 40 twice and successfully caught a shiny Flabebe and a shiny Weedle. I no longer care as much about learning what rules do and don't apply, but for anyone that's curious, for both of those successful chains I ignored the "don't go to patches when an adjacent patch is also shaking" rule and the "only go for a patch when you can see five shaking" rule.

If anyone still wants to discuss the ins and outs of this method (or any other shiny catching method), I'm always happy to talk about that kind of thing.