Overgripping?

[*gatevaulter]

I have been using this pole for about a year now with different results depending on what I do. I am a junior in college with not much access to any different poles. This is a 14'6 155 and the next biggest pole is a 15 155 which I am struggling with. I am gripping 13'6 in these videos. Is that too big of a jump? Should I try going with shorter stiffer poles? I have changed the way I jump a few times this season (I have focused on holding the takeoff for a split second and extending my arms [first two vids] and I have always tried swinging immediately to get inverted asap [second two vids]). Any help/advice would be greatly appreciated.

https://www.youtube.com/watch?v=gw4e8er5cXQ (lost a little control up top on this one)
https://www.youtube.com/watch?v=aUlaOZsf31Q

https://www.youtube.com/watch?v=_axlK6__PkM
https://www.youtube.com/watch?v=E-0j5EpAEK8

Thanks!
Dave