Lomdus in Tefillah

In one of my previous posts (here) I discussed the lomdus of selichos. In that post I quoted Rav Soloveitchick that there are two types of tefillah. There is the formal tefillah of shemoneh esrai and the informal tefillah of selichos (called zeaka - crying out to Hashem).
What is fascinating about this piece is how much of it can be derived from analyzing the siddur itself, with no other needed outside knowledge. Consider the fact that most of the vort is derived from the following points:

1. Both selichos and shemoneh esrai are followed by a kaddish with tiskabel.
2. Both selichos and shemoneh esrai are followed by a tachanun. (Here it may help to know that the Rambam says that tachanun merges with shemoneh esrai, but is this knowledge absolutely necessary?)

These are the similarities between the two. Here are the differences:

1. Shemoneh Esrai is silent, with feet together, and a standard nusach.
2. Selichos has none of these elements.

At this point it may help to know the Rambam's categorization of zeaka, but, again, it isn't necessary.

What I am pointing out is that the siddur is it's own entity that can be analyzed even without resorting to other sources. The lomdus of the siddur can be derived with a very "local" analysis. So next time you pick up a siddur, try to see it through a lamdan's eyes!