Can LDS Temple ordinances have “power?”
It is an interesting question. The answer depends on each individual who participates. The ordinances can be either meaningless (or worse) or they can be beneficial.
Temple rites communicate information through symbols. If we look at the underlying meaning, and see more light and truth through them, then they can powerfully instruct and edify.
The rites warn us we need to be “true and faithful in all things” when we seek “further light and knowledge by conversing with the Lord through the veil”–which is very good. Faithfulness to what light we’ve been given is a prerequisite for getting more light. Knowing that gaining further light and knowledge is possible, actually expected, is essential. Believing that God will converse with us is also foundational to salvation.
Perhaps the greatest idea is that we can converse with God through the veil preliminary to entering into His presence. In that idea is found the promise of communication with God, followed by Him allowing us to visit with Him through the veil. Every soul who has faith in that and acts consistent with their faith will obtain the most glorious assurances from God. They will not be barren or unfruitful in their knowledge.
If the rites are viewed as some authoritative guarantee of something in the afterlife, without regard to our need to search, they can be destructive. Instead of a humility and meekness before God, the false idea that the rites make you special, chosen or better than others can lead to pride and arrogance. That separates us from God. It increases the distance between ourselves and the light of truth. Such an approach makes the rites a tragic and negative misstep instead of a blessing.
I would encourage everyone to reflect on the message of the temple rites. In the right frame of mind, their symbols are useful. The form presently presented in LDS Temples is still a useful collection of symbolic teaching about the mortal quest to find God.