It's full time oiling, and restrictors are easily changed if you want to increase/decrease the flow to the top end....... Without resorting to either a grooved #4 cam journal or bearing...... Both of which take oil away from the #4 main.

I look at the external lines that are used on some Indy heads as an item in the "pros" column.

Cost considerations aside, I think it would make for an interesting test to compare some TF240's against some similarly flowing std port SR's on a 700hp-ish 505 or 511.
The SR's have such differently shaped intake ports than the TF, along with a raised, better flowing exhaust port........I'd love to see how that would play out.
Would it make any real difference or not?