  The rapid variability of the VHE emission reported for some TeV blazars
implies Doppler factors well in excess of those inferred from superluminal
motions and unification schemes. We propose that those extreme flares may
result from radiative deceleration of blobs on scales where local dissipation
occurs. The minimum jet power estimated from the resolved synchrotron emission
on VLBI scales appears to be consistent with this model. It is shown that if
the energy distribution of nonthermal electrons accelerated locally in the blob
is reasonably flat, then a background radiation field having a luminosity in
the range 10$^{41}-10^{42}$ erg s$^{-1}$ can give rise to a substantial
deceleration of the blob, but still be transparent enough to allow the TeV
$\gamma$-rays thereby produced to escape the system.
