The generally accepted mechanism that is proposed in most reported radical fluorination methods involves the radical of the substrate, resulting from HAT between the substrate and TEDA 2+• (Scheme 1, C). In almost all previous reports, a chain mechanism is drawn and inferred, however, no evidence for a chain mechanism was actually provided. To the contrary, Lu, Soo, Tan and co-workers 8b measured a very low quantum yield for their photocatalytic C(sp )-H fluorinations. Later, Baxter 11 also contested a possibility of radical chain mechanism after showing how stoichiometric (and not catalytic) amounts of glycine were necessary for product formation. Owing to on-line NMR irradiation capability, our team discovered an induction period for these reactions that is likely a general phenomenon for all photochemical C(sp )-H fluorination reactions. Obviously, the mechanistic situation is more complex than it was previously depicted. Protodefluorinated Selectfluor ® (H-TEDA(BF 4 ) 2 ) is the byproduct of any fluorination reactions using SF ® as an electrophilic fluorine source (Scheme 2, A), and the former is always discarded as waste. According to Research Excellence Framework 2014 report concerning the institution where SF ® was discovered, 15 SF ® is the world's most popular organic fluorination reagent in industrial processes -with annual worldwide production reaching ~25 tonnes (as of 2014). However, with 95% of its M.W. discarded in fluorination reactions, this could generate as much as ~24 tonnes of H-TEDA(BF 4 ) 2 waste per year. If the H-TEDA(BF 4 ) 2 waste could Herein, we report the discovery of H-TEDA(BF 4 ) 2 's hitherto unknown function as a cheap and recoverable performance additive that improves the efficiencies of a diversity of fluorination methods by altering the aggregation state of SF ® (Scheme 2, B). We exemplify this for both thermal and photocatalytic fluorination studies where H-TEDA(BF 4 ) 2 markedly increases the efficiency, rapidity, and practicality of C(sp 3 )-H fluorination reactions. A highly attractive feature is that the H-TEDA(BF 4 ) 2 can either be authentically synthesized from cheap DABCO or isolated as a 'waste' product from radical fluorination reactions, both approaches being feasible, high yielding and even tracelessly executed on a gram scale. The latter approach allows to upcycle a waste product that is until now discarded after radical fluorination reactions, to improve the efficiency of those very reactions.