@hifi369 You absolutely can. The spec lines out the generalist option but if you ever want to hard commit to deeper talents within a tree simply abandon Imp Healing Wave and Healing Way and commit yourself to CH and LHW as your throughput options.
The reason I like that spec and like having the "Deep Resto" talents is that, in case anything ever goes sideways or on progression where something unexpected occurs, you can switch roles and solidly tank heal. This is less true in Classic for some but equally as valuable as a player. I personally use the Healing Wave talents <1% of the time, however, when I needed it, it was there. If you want to specialize, no disagreement at all. Just know the cost of the trade.