As is clearly visible from Table~\ref{tab:FitResults} and Fig.~\ref{fig:FitResults}, a model-independent precision systematically better than 1\% (and at times approaching the per-mil level), required for the coupling measurements to become sensitive to (multi-)TeV new physics, can be obtained with the TLEP high-statistics data samples. The luminosity expected to be produced at linear colliders is insufficient for this purpose.

It is also important to compare the projections of TLEP to those from the HL-LHC, as to evaluate the added value of a circular $\epem$ Higgs factory after $3~\inab$ of proton-proton collision data. A truly model-independent fit cannot be performed from proton-proton collision data: the total decay width cannot be easily determined with the sole LHC measurements and the ${\rm H \to c\bar c}$ decay likely cannot be isolated by the LHC detectors -- although new ideas are emerging on these two fronts~\cite{1208.1533,1305.3854,1306.5770B}. Additional assumptions thus need to be made for a meaningful comparison with $\epem$ Higgs factories. Here, constraints similar to those used in Ref.~\cite{Barger_Ishida_Keung_2012} are applied: it is assumed that no Higgs boson exotic decays take place, and that deviations of the charm and top couplings are correlated.  The CMS report~\cite{1307.7135} submitted to the recent Snowmass process contains estimates of the CMS projected performance with $3~\inab$, with similar hypotheses, in two scenarios: Scenario 1 with all systematic uncertainties unchanged, and Scenario 2, with experimental systematic uncertainties scaling like $1/\sqrt{L}$ and theoretical errors halved. These estimates are displayed in Fig.~\ref{fig:HLLHC} and compared to a fit of the TLEP projections made under the same hypotheses.


