javascript - Adding MathML String to DOM very fast best approach?

Question

What I do: I go through the DOM and translate e.g. Latex strings to MathML. This is very quick with Mathjax.

But we inject the generated MathML string

mathStr = jax.root.toMathML();
return jQuery(mathStr);

to the DOM and basically this last jQuery call makes everything slow for me.

Is there a way to get a tree instead of a string similar to toMathML() in a faster way? Or is there a faster way to transform a MathML String to a tree?