When using Barry's speed, Grodd is seen phasing and running at the same time. However, it was previously established that Barry could not use these abilities at the same time.
However this could be due to Oliver unlocking Barry's full potential or Grodd having a higher knowledge of Barry's abilities than Barry himself.
During the fight with Solovar, Frost tells Kamilla and Chester that Solovar is winning, despite Barry only having said that they were fighting a gatekeeper.