[I have heard the argument that if you feed the bees will raise brood and not make honey.]
[I don't think there are enough to cover both sides of a frame. ]
Bees must have themselves well established before concentrating very heavily on foraging.
If your population is as small as you say, their likely focus will be brood rearing anyhow.
You will cause them no damage by providing them with better nutrition.
While some older bees could be pulled from foraging, the colony will never pull more than it needs and never more than would cause detriment to 'needed' colony stores. Colonies don't like taking older bees, they get beyond a point of providing good larval care (less royal jelly production, etc.).
If it impacts the honey crop you were going to pull, then likely the colony is in a weak enough state that you should nurse it first.
[My (limited) observation is:]
If you are observing the bees, that's as professional as advice gets.