Hey Jon S. I think you are confusing two different things. The baptism with the Holy Spirit (BHS for short) is a pneumatological event. It is “an enduement of power.” For Pentecostals, this empowerment results in “an overflowing fullness of the Spirit, a deepened reverence for God, an intensified consecration to God and dedication to His work, and a more active love for Christ, for His Word and for the lost” (Assemblies of God Statement of Fundamental Truths). Some Pentecostals believe in what is called “the doctrine of initial evidence.” This simply states that along with all of the other evidence for Spirit-empowered Christian ministry an immediate and physical sign will be speaking in tongues.
None of that has anything to do with fainting. It can be quite emotional for some people. But for others it can be a quiet, gentle move of the Holy Spirit. The Holy Spirit does not violently possess us like some demonic power. The Holy Spirit does not compel; he leads. Anytime God moves in us, he will work through our personalities. Where the Spirit of the Lord of is there freedom, that includes the freedom to let God work through us as we are.
Some seem to focus on the external stuff that is happening, the “spiritual acrobatics.” However, those are physical manifestations. It is that person’s reaction to the presence of an infinite and glorious God at work upon a finite body.
This is a minority view within global Pentecostalism. It’s mainly associated with the Oneness Churches. The vast majority of Pentecostals are pretty consistent in what salvation is and how it is attained.
To put it simply, speaking in tongues is pneumatological, not soteriological.