Good points all around. I think part of the trouble is that the character was a Park Ranger before getting called to Serve, so the concept is kind of pulling in two directions at once. And maybe I'm being too stingy about thresholds, but most of their big indoor battles have taken place in public builds, which by the book don't really have Thresholds. I have let him treat buildings as having a 0 Threshold before and he seemed to lack that, which is why I asked about this.
A few points of correction here. Per YS187, Bless This House give a boost of +2 to any
place with a Threshold, assuming the player's Conviction is higher than the Threshold rating of the place. This power is also stackable with others having the same power at the same place.
Now, per the rules on Thresholds from YS230-231, the most commonly thought of definition of a Threshold is the one which is part of a 'home' but it is NOT the only definition of a Threshold. Public buildings (office buildings, hotels, etc) tend to have Mediocre (+0) Thresholds from YS231, which effectively means the Threshold provides no impedance to supernatural energy. However, a character with Bless This House and a Conviction of at least Average (+1) would immediately cause any public building they were in to have a Threshold of Fair (+2) just by being present. If the character were to have a Conviction of Great (+4) or higher and be in an 'average' church of other similar building of worship/faith, the Threshold would immediately climb from a default Good (+3) Threshold for an 'average' church up to a Threshold of Superb (+5).
Other potential examples of Thresholds where a player might find Bless This House useful include the Threshold of a stream. If there was some supernatural nasty on one side of a stream, and the character was on the other side/bank of the stream, the presence of the character with Bless This House again automatically 'improves' the Threshold of the stream as long as the character's Conviction is higher than the Threshold value of the stream. I would expect a Park Ranger to be places where there are streams/running water. Lastly, from Bob's sidebar on the left-hand side of YS230, magical circles could be considered Thresholds. With that in mind, all a character with Bless This House would need is a drop of blood, a piece of chalk, a bag of salt, or something else to 'draw' a circle with and the circle would pretty much automatically get a +2 boost to strength. Given the sort of players I have, even at convention games, any characters who are considered 'in the know' are always running around with a piece of chalk, salt, iron filings and a knife in a pocket or bag. Therefore, such a circle could be drawn by the character virtually anywhere and on an as-needed basis. Not too weak a power from my perspective.
-Cheers