I find that a clench rotation is easier on resources than one with frags. The damage potential is about the same though according to my tests (check post #17 https://forums.elderscrollsonline.com/en/discussion/375949/magicka-sorcerer-dps-what-am-i-doing-wrong-video-included). I personally prefer to use force pulse, because it allows more flexibility since it can be used at any point in the rotation, and doesn't have to be timed perfectly with all the other spells, but of course that means somewhat lower overall dps.
Clench for heavy attack builds . Frags for Force Pulse builds .
Clench for heavy attack builds . Frags for Force Pulse builds .
Pretty much this.
On the other note on my petsorc I also tested shock reach as a spammable combined with master lighting staff (in place of moondancer lighting staff as a fourth set piece). With this setup I got nearly 41k on a dummy so if someone is tired of spamming HA/FP (depending on a build), master lighting staff with shock reach spammable is a decent replacement (yet ofc still weaker than e.g. moondancer staff as a fourth set piece) and feels like a breath of fresh air.